SPONGES and JELLYS
I Spongy Landscapes
by PETER V. CHETIRKIN
The marine environment is an incredible conglomeration of dynamic living systems all seemingly interrelated and organized into a beautiful and sometimes unusual harmony. Some of its inhabitants are destined to be bottom dwellers. Seemingly motionless, covering large areas of bottom substrate, and creating some of the most colorful and unusual landscape artistry imaginable.
One such inhabitant, sometimes referred to as the “pore
bearer’S or “filter of the sea,” is the sponge. These invertebrates can be
found over large areas of bottom substrate including corals, both living and
dead, rocks, ledges. shells, gorgonians (soft corals), and other hospitable
surfaces. Of the three classes comprising the sponge phylum (porifera),
Demospongiae is the largest both in species numbers and in range of distribution.
This class contains most of the colorful sponges encountered on coral reefs
and back reef communities off the Florida Keys and throughout the
Although some sponges are radially symmetrical the vast majority, are irregular, displaying sometimes massive, erect, encrusting, or branching patterns. These unusual forms are in part due to environmental conditions such as substratum currents, sediments, and wave actions. Changes in these conditions can cause a species to produce a variety of appearances which makes identification difficult. The relationship between the animal ‘s surface area and water volume was an important factor in increasing the size of sponges as they evolved. In the more primitive sponges, referred to structurally as asconoid, the flow rate of water is very
slow because the internal cavity (spongocoel) contains too much water to be expelled rapidly. Therefore, as the sponge increases in size water movement is intensified, and since the surface area does not increase, the sponges stay small. However, during their evolution some sponges began to fold their body walls thereby reducing the internal cavity and at the same time increasing the surface area which promoted greater circulation. This caused the sponges to dramatically increase in size. These sponges, referred to structurally as leuconoid, cover large areas of bottom and create remarkable forms and structures.
The surface of sponges is an assembly of minute pores (incurrent waterways) with sometimes towering openings called oscules (excurrent waterways) covered by an epidermal layer within which calcareous or silicious spicules and organic fibers are distributed. These add to the framework and to the surface texture which can sometimes be stoney to the touch. Drabness is often unjustly associated with sponges. Yellow, orange, red, purple, and green sponges are frequently encountered. These colors are due largely to pigment granules associated with certain cells called “wandering amebocytes,” located beneath the epidermis in the mesenchyme layer, a gelatinous protein matrix. Besides the pigment granules, sponges sometimes exhibit color patterns due to relationships with other organisms. In some sponges, green coloration is due to a microscopic algae called zooxanthellae. This symbiotic photosynthetic algae is brought in through the incurrent pores and then transferred to the amebocytes. The surface of the sponge is a playground for a variety of organisms including sea anemones, marine worms, starfish, and zoanthids. One such frequently observed association is that of an anemone-like organism called zoanthids. These occur as colonial or solitary, symbiotic or free living. One zoanthid in par-
ticular, Parazoanthus parasiticus. although occurring on a wide variety of sponges, is often encountered on Cliona delitrix, an encrusting or burrowing demosponge which cover sometimes up to 4O inches of substrate. Cliona are bright red to reddish orange with large prominent oscules scattered over the surface. Close examination reveals minute zoanthids uniformly dotting the spongy landscape like flowers in a meadow. They occur as single polyps or in groups of no more than two or three. The column of the polyp is white because of the calcareous sand encrustations resulting from the coral chipped away and dissolved by the sponge.
Marine worms are also frequently seen on sponges. While burrowed in the sponge some of these worms extend colorful feather-like gills called radioles.
This ubiquitous and ancient animal whose existence can be traced back two hundred million years, was unable to give rise to new forms and is destined to exist as it is. Its nature and unique associations, adaptive mechanisms and a wide range of habitats allows it to react to subtle changes within its environment resulting in an incredible display of interesting forms and amazingly colorful landscapes.
II Common Jellyfish
of the Middle
by DOROTHY JEFFRESS and FRANK STEIMLE
Vol. 19, No. 2
Every summer the public makes its annual migration
to the shore, and people find that they have to share the waters with its
natives, some of which they deem undesirable. When people come into contact
with jellyfish, they express a variety of questions and concerns, such as: Why
are they there? Are they increasing because of pollution? And, what does one do
if stung? We will answer some of these questions and provide a brief review of
the several common species occurring in the waters from Cape Cod to
Jellyfish is the name commonly given to any organism that is pelagic (lives in the water column), contains mostly water (93%), and has a jelly-like consistency. However, there are several different types of organisms included in this vernacular classification: Christmas light-like siphonophores, true medusa types, and “sea walnuts” or ctenophores. Most shore visitors see only the latter two groups.
Most true medusa-like jellyfish (scyphozoa) are semitransparent and glassy. They often have brilliantly colored tentacles, internal digestive canals, or egg sacs, and are often photographed for diving magazines. Each tentacle of a medusa jellyfish has thousands of tiny stinging cells, called nematocysts. These jellyfish have unusual life histories that include several different forms, some pelagic and some attached to the sea bottom. Also, every other generation is asexual. An anemone-like or polyp form buds new disc-shaped individuals that develop into sexual medusa forms which in turn produce eggs that develop into larvae (planula). These settle to the bottom to become the attached anemone form, again.
Nearly all adult medusae are free swimming and occur in most seas, although some species do live on the bottom in tropical areas, e.g., the “upside-down” jellyfish of the Caribbean mangrove lagoons. Because their swimming ability is relatively weak, medusa are greatly influenced by currents, tides, and the wind, and are often common where currents converge. They can use their pulsating bells to rise in the water column or to sink to search for more favorable conditions.
Most medusa are active carnivores and if present in great numbers can seriously effect the survival of the eggs, larva, or young of fish and other sea-life. Small planktonic crustacea and other jellyfish are common food, as well. The stinging cells on the tentacles are for capturing food not for making life miserable for bathers.
Medusa jellyfish can be useful to man. Some species are harvested and dried for consumption in the Orient. Also, many sea turtles feed heavily, if not entirely, on jellyfish. Many sea turtles die by eating clear plastic bags they mistake for jellyfish. Several fishes (spiny dogfish, chum salmon, Atlantic mackerel, and cods) also eat them, despite their low food value.
There are three common medusa type jellyfish in the Middle Atlantic area: the sea nettle, the moon jelly, and the large lion’s mane.
Chrysaora quinquecirrha, the sea nettle, or summer jellyfish, is the dominant and conspicuous jellyfish of the bays and
estuaries where it tolerates a wide range of salinities. This jellyfish is typically bell-shaped and pale white, sometimes ribbed with reddish markings that resemble numerous wheels pulsating along the surface; long thin tentacles edge the bell. The species is familiar to both fishermen and swimmers because of its abundance in the summer and its sting.
The sea nettle spends most of its life cycle as a sessile polyp attached to the underside of oyster shells and other hard surfaces in coastal areas where they will not be smothered by silt. Small sea slugs or nudibranchs find them an irresistible snack. The mini-medusa bud off the polyps and are abundant spring through fall. They are not without enemies. The harvestfish, Peprilus alepidotus, a relative of the butterfish, is commonly found swimming in and out of the deadly tentacles with apparent impunity and feed
heavily on them, as well. Larger fish can destroy a jellyfish in minutes.
The moon jelly, Aurelia aurelia, is one of the most common and widely distributed medusa. It is translucent white or tawny and several inches in diameter. When found washed upon the beach, they look like the bottoms of old glass milk bottles, with a clover-like pattern often evident. They also make their appearance in the spring.
The adult moon jelly does not have large tentacles or significant stinging cells, so it does not sting us. It collects planktonic food through rows of fine, hair-like cilia that sweep food to the mouth at the center of the underside. It will catch and eat other small jellyfish and other small planktonic critters. Moon jellies can catch larval fish and shellfish and have been considered by some to be involved in the decline of herring in the Baltic. When they are abundant, they can also affect fisheries by clogging nets.
Relatives of the lion’s mane, Cyanea capillata, can grow to over 10 feet in diameter and have tentacles over 100 feet long. The lion’s mane jellyfish is the largest medusa commonly found in the northeast, being about a foot or more in diameter. It is relatively thick bodied, thus another name for it — sea blubber, and colored from brown to red-purple with a large amount of curtainous material (digestive or reproductive organs) beneath the bell. This and the abundant tentacles make up the “mane.”
It is also found in northern waters and in abundance along the shore in the early summer. Tides and currents are responsible for great windrows of them being washed up on the beach in some years. This species can produce a stronger sting than the other two common species, although not nearly as strong as some tropical species.
It feeds on larger planktonic forms, including juvenile fish. Juvenile cod, haddock, whiting, and some mackerel are commonly found associated under the medusa bell and between the oral arms, somehow avoiding the ring of deadly tentacles.
The comb jellies are not disc shaped, but usually globular or somewhat compressed and represent a different phyla, Ctenophora. They are not large and one of their names, sea walnuts (sea kiwi fruit for some of you), is an appropriate estimator of size and shape, but not color. They have a variety of translucent tints, and the eight rows of ever beating cilia (the combs) along their sides make them glisten or iridescent. Many are luminescent.
Comb jellies have no stinging cells although some species have a pair of sticky tentacles. Thus they are harmless to man, they also do not go through a sessile bottom phase, and are poor swimmers which make them subjects of the whim of tides and currents. Rows of
cilia sweep planktonic organisms into the comb jelly’s mouth which is located at one end where the rows come together.
The most common species of comb jellies in the northeast are the sea walnut and the sea-gooseberry. The sea walnut appears in the late spring and early summer and flourishes throughout the warmer months so it is the species that most summer visitors to the shore see in the surf as little blobs of jelly in the waves. The other two common species prefer cooler temperatures.
The sea walnut, Mnemiopsis leidyi, often occurs in large swarms famous for their luminescence. They are not as innocuous as they may appear since they feed on mollusc larvae that could include valuable shellfish. When they occur in estuaries, they can be controlled by sea nettles, the jellyfish swimmers could do without but that oystermen and clammers recognize as a potential friend. If abundant and not controlled they also can have a major affect on estuarine planktonic ecosystems by reducing the zooplankton that feeds on and reduces overabundant microscopic algae blooms.
The Beroe comb jelly, Beroe ovata, has a conical, compressed body with a large mouth at the bottom. Generally pink in the north and paler farther south, it does not occur commonly above Cape Cod and is most abundant near Delaware and Chesapeake Bays. This comb jelly swims in circles searching for prey. It feeds on other comb jellies that it sucks into its mouth and swallows whole.
The sea gooseberry, Pleurobranchia pileus, is truly berry-like in shape and almost transparent, although there can be tints of color on some parts of the body. It has two long, branched tentacles that it can retract into a pouch between the rows of cilia. This is a cold water species and is common south of Cape Cod only when winds and storms sweep them south.
They are passive drifters and catch their food (smaller planktonic organisms) on their tentacles. They are reported to be voracious, and swarms can sweep the waters clean of smaller plankton.
Now that you are familiar with “the cast of characters,” we’ll answer some common questions about them.
Why do jellyfish appear to swarm near the beach during the summer? All varieties of jellyfish are weak swimmers and at the mercy of the tides, winds, and currents. They are frequently found where currents converge. The surf zone is not a healthy place for their fragile bodies so it is only by chance that they end up there or on the beach. Either offshore or onshore breezes can bring them in, depending on whether they are at the surface or near the bottom of the coastal water layer.
How dangerous are these jellyfish and what should one do if stung? The medusa type jellyfish are the only ones to be concerned about because of the stinging cells on their tentacles. The sea nettle and the lion’s mane are usually the only commonly occurring species that can be a problem to bathers and fishermen. South of Cape Hatteras there are other species, including the Portuguese man-of-war and sea wasp, that are more potent. The stinging cells of the moon jellies are seldom felt by humans. The jellyfish stings when the microscopic nematocysts on the tentacles are touched causing them to evert a long, thin, tube-like dart at whatever has triggered them. This dart contains a numbing poison intended mostly to subdue its prey, but can also be for the jellyfish’s protection. When these stinging tubes penetrate the skin they cause a mild to severe local itching or burning reaction. Even tentacles broken off in the surf and lying partially dried and nearly invisible on the beach can still be “loaded” and give a sting. The soles of our feet are usually thick enough for protection against these stings, but children playing in the sand containing tentacle fragments may be irritated.
This irritation is seldom more than a minor, temporary rash, but certain especially sensitive people should be more cautious. For these people, the rash can be accompanied by other symptoms, such as fever and chills, headaches, intense pain, and nausea or diarrhea that can persist for several days. Repeated exposure to jellyfish stings have lead to allergic sensitization for some, possibly resulting in anaphylactic shock, a severe condition requiring immediate medical attention. If you are concerned about stinging jellyfish in an area, ask a lifeguard and make sure he/she knows the importance of a correct answer.
But for most, minor jellyfish irritations are like mosquito bites, the small price we pay for being near the water in the summer. There are a number of “home” remedies to reduce the reaction and the irritation. These include sprinkling the area (after washing with salt water and carefully lifting off any adhering tentacles) with ammonia, vinegar, lemon juice, baking soda, or meat tenderizer. This is not to make you more digestible to the jellyfish, despite what some say.
The meat tenderizer contains enzymes that are reported to neutralize the protein toxin. It may be that just altering the pH of the affected area provides some relief. There are commercial preparations, such as cortisone or other analgesics available in pharmacies. Medical attention should be sought if the irritation is severe or persists for more than an hour or so.
Is pollution causing an increase in the abundance of jellyfish? Some scientists think that this might be partially true because nutrient or other pollutants can alter the coastal food webs so that the smaller plankton species become more abundant. These are good food for certain jellyfish and not for other larger plankton feeders. This idea is not held by all and needs to be examined further. There have been reports of great rafts of comb jellies occurring off New Jersey and Cape Cod in the first two decades of this century, where pollution would not be expected to be extensive. However, jellyfish are reported to be adversely affected by some chemical pollutants such as toxic metals.
Can jellyfish cause other problems? Sometimes when they are very abundant in estuaries, they can drastically reduce the populations of small crustaceans that feed on the seasonal phytoplankton blooms. So instead of the phytoplankton being eaten and integrated into the food web, it sinks to the estuary bottom and dies. The accumulation of dead phytoplankton (and the jellyfish themselves after they have eaten everything and starve) can contribute to the development of local anoxia (no or little oxygen left in the water) conditions that can kill some organisms and chase away others. Also, as previously noted, abundant populations of jellyfish can eat a lot of larvae of species that we would like to see survive, like harvestable fish and shellfish.
The jellyfish are another remarkable group with which we share the planet and, although not always friendly, deserve to be appreciated for their beauty and how they make their living.
(taken from National Geo. 8/94 by William Haner)
Jetting through water, a box jellyfish looks as harmless as cotton candy. But this scourge of the beach-also called a marine stinger or sea wasp-is earth's most venomous creature. Contact with its tentacles can bring agonizing death within four minutes.
Shimmering in the glow of flood lamps along the pier, two large ghostly shapes undulate just beneath the surface of the dark sea. Webs of long, almost invisibly thin tentacles swept out behind their box shaped translucent bodies. It was Chironex fleckeri, the infamous box jellyfish found in the near-shore waters of Australia and southeastern Asia.
Difficult to see, these cubic phantoms have long cast a dreadful shadow over the sundrenched beauty of the north Australian coast. Known also as sea wasps or marine stingers, box jellies have killed at least 65 people in the past century. They are the most venomous animals on earth since no other animal's venom can kill a human in 4 minutes or less. Australia's most dangerous snake, the taipan, has enough venom to kill 30 adults, but its bite is not very painful, and it can take several hours for an untreated victim to die. A large box jellyfish, however, has enough venom to kill 60 adults and the pain of its sting is instant and unbearable. Breathing may quickly become distressed as venom is absorbed into the circulatory and lymphatic systems: in some cases, the heart's pumping slows or stops almost immediately.
Trying to study these animals was a task and watching these two large Chironex under the pier, never touching the oyster encrusted pilings that would easily tear their delicate tissue, was a chance to catch these to study their life styles. Using a long-handed net to scoop them up into the waiting buckets, a breeze caught a single tentacle still dangling outside one of the buckets. The collector was stung in the inside of his arm and felt at first he had been branded by red-hot steel. A fiery welt, braided with the characteristic bands of the box jelly's tentacle, appeared. He was lucky as only about an inch of tentacle had struck on his arm. It takes ten feet or more to deliver a fatal dose of box jelly venom.
In order to study the life stages of Chironex, it is necessary to know the life stages of other jellys. Other jellyfish begin their life as mobile little balls of cells called planulae, which settle on rocks or other hard surfaces and transform into polyps--tiny organisms with a crown of tentacles. But in 1977, when the above work was done, no one had ever seen either Chironex planulae or polyps. It was noticed that the stress of capturing them caused them to release their sperm and eggs into the buckets. Using these sperm and eggs released into the bucket, the possibility of getting fertilized eggs was studied to see if the planulae larva and polyps may form.
The biologists soon had tanks, jars, and plastic dishes brimming with planulae but the organisms soon died after transforming into microscopic polyps. It was known the planulae need a solid surface to attach but they rejected all rocks, mollusk shells, coral and mangrove roots offered to them but found the polyps were thriving at the bottom of the tank.
Now that the juvenile forms of the box jelly were identified, the next step was to find them in the wild. This would prove laborious because of their small size and because no one knew where breeding occurred.
Since Chironex medusa appear only in the Australia summer, some biologists thought they migrated south from New Guinea. Others suspected hey might spawn between the mainland and the Great Barrier Reef, some 40 miles offshore.
After months of collecting million of cubic meters of seawater, they found the youngest and smallest medussae were closest to the mainland, indicating their spawning grounds were nearby. Later, Chironex medussae were found three or four miles into such estuaries and streams as Alligator Creek. In 1980 they started collecting mollusk shells and pieces of mangrove roots to examine for polyps under the microscope. After looking for thousands of rocks from 14 rivers for six years, sometimes taking as long as four hours to examine a four inch rock, they finally found a rock with polyps that looked just like Chironex polyps.
Over the next 12 days, the length of time it takes for box jelly metamorphosis, they eagerly watched as each step from polyp to medusa matched what they expected. Finally, when the medusa emerged, they were unquestionably tiny box jellies.
Thanks to their work, we can now describe the entire life cycle of the box jelly. Adults aggregate in river mouths and estuaries in late summer to spawn and then die. The resulting planulae settle onto the bottom, where in the fall they transform into polyps and colonize the undersize of stones, creeping along to find a suitable spot to anchor. During this time, new polyps may sprout from existing polyps. In the spring, the polyps become little medussae, migrating seaward before monsoon rains set in. At sea they feed on prawns and fish, but their favorite food is a small shrimp that schools close to shore--along the same sandy beaches that Australians find so attractive in the summer.
And therein lies the problem. Chironex do not intentionally sting humans, of course, but simply react when their tentacles are brushed. Jellyfish tentacles have specialized stinger capsules called nematocysts, each of which has a mechanical trigger. To fire, however, the nematocysts must be stimulated chemically. That stimulation comes from chemicals found on the surface of fish, shellfish, and unfortunately, humans.
The slowly pulsing translucent bells are hard enough to see as the medusa as the medusa troll for prey in northern Australia's murky coastal waters: their tentacles are even harder to see. Fifteen feet long and only a quarter of an inch thick, they stream behind the bell like invisible fishing lines. In fact, not until 1965, was the species Chironex fleckeri actually described and identified as the creature that inflicted such agony. Stories abounded of swimmers running from the water screaming, tearing at lesions on their skin but never having seen their assailant.
Fortunately for tourism, box jellies don't live on the Great Barrier Reef, where about a million visitors swim throughout the year. Nor do box jellies haunt the beaches of Australia's Gold or Sunshine Coasts near Brisbane. But summer beachgoers have had to adjust their behavior to the presence of the lethal jellyfish along the shores north of the Tropic of Capricorn, which passes near the city of Rockhampton in the northeastern state of Queensland.
When people do bathe along vulnerable beaches, they should either swim in safely netted areas or wear protective clothing. Entrants in surfing competitions have been known to wear 2 pairs of panty hose-one covering the legs, and the other upside down, with the wearer's arms thrust through the pantyhose legs and head poking through a hole in the seat.
How can the ultra thin pantyhose fabric protect against the venom? The stinger capsules are too short to puncture skin covered by the hose. That's fortunate because although each nematocyst injects only a microdrop of venom, a single tentacle contains millions of the deadly capsules.
This is how the box jellies are can be so difficult to treat. Snakes and spiders usually only bite only once in a single spot, but the box jelly venom enters a victim over a large area. There is an anitvenom that was developed 24 years ago by Australia's Commonwealth Serum Laboratories, who injected sheep with non-fatal doses of venom. The sheep produced antibodies that can be used to manufacture antivenom. Medical personnel in coastal regions of the Northern Territory and northern Queensland carry the antivenom.
When injected intravenously, normal breathing often begins immediately, and pain relief usually occurs within minutes. Later scarring is frequently reduced.
Attempts to keep cube jellies in captivity usually fail because they just won't feed in captivity. A new kind of aquarium called a planktonkreisel (plankton carousel) which rotates water in a way to prevent jellyfish from becoming trapped in corners and the drains. As soon as the jellies were put into these aquariums, they began to swim in a circular pattern with their tentacles stretched out behind them--something never seen in still water tanks.
When live shrimp were put into the tank, one of the Chironex's tentacles soon touched a spiny banana prawn, which died instantly. Entangled in the tentacles, the shrimp was reeled in close to the box jelly's pedalium, a feeding appendage that lifted the shrimp up to the medusa's reaching mouth. At last an environment to allow scientists to observe living, feeding box jellies had been developed.
Watching the box jellies eat the banana prawns, it was quickly appreciated why Chironex needs to be so lethal. Prey such as banana prawns are covered with sharp spines which if eaten alive, one flip of their powerful tail would rip the delicate tissue of the jelly to pieces. It is far better to kill quickly.
One observation of the Chironex in the tank was that when room lights were bright and the observer had dark clothes on, moving toward the tank would swim away from that side of the tank. Such behavior in an animal as simple as a jellyfish was unlikely though box jellyfish do have structures that greatly resemble the eyes of vertebrates. Could their nervous system be complex enough to process visual information?
Sealing off the aquarium so that no light penetrated from the outside, various targets were presented to the jelly. Because the target was black to contrast with the white wall of the tank, each time, the jellyfish turned away. These experiments demonstrated that box jellies can see very well, though no one knows how they do it.
After these experiments, the scientists went back to that pier in the beginning of the story. They observed the jellies pulsing toward the pier when three large green turtles appeared. The fastest of the three turtles consumed the jelly in two quick bites.
This creature that can kill in an instant was being casually dined on, tentacles and all, by an enemy obviously immune to its defences. How did the sea turtles do it? Perhaps there is some protection afforded by the lining of their digestive system--which may also be what allows them to eat glass sponges with ease.
So even this most venomous creature has its own vulnerabilities.
IV SEA LICE or Seabathers Eruption
Adult Thimble Jellyfish (Linuche unguiculata)
CLINICAL ARTICLES SEABATHER'S ERUPTION OR "SEA LICE":
New findings and clinical implications Mary T. RusselI, RN, MSN, CCRN, CEN, and Robert S. Tomchik, MD, MPH, Boca Raton, Miami, and Fort Lauderdale, Florida.
For the past 11 years, during the months of March through August, residents and tourists along 250 miles of Florida's southern Atlantic coastline have complained of an annoying pruritic rash, primarily within areas covered by bathing suits. Although this problem has existed since the early 1900s at least, it has not been formally recognized and understood until recently. The first study (a retrospective case review of ED cases seen during 1992) and a sample population survey were conducted at Boca Raton Community Hospital. The outbreaks appear to have intensified in the last 4 years, as reflected in the number of cases reported as well as the severity of response in individual cases. Because most affected people treat themselves, it is difficult to determine the total annual number of cases. However, a conservative estimate of 10,000 cases in 1992 can be made. A sample population survey of 1433 persons who went swimming within the apparent geographic center of the outbreaks indicated that one of every four persons that went swimming had the dermatitis. Because the Sunshine State has a significant tourist population, people who have the rash return to their respective states or countries, seeking follow-up care from their local health care facilities. This has prompted calls to Florida's Public Health Offices and emergency departments, requesting information as to the origins of the rash and recommendations for treatment. Many persons expressed confusion and fear that they had contracted a communicable disease, such as venereal disease, chickenpox, or measles.
Periodic outbreaks have existed before this decade, and it is possible that this form of dermatitis has been around for centuries. Fishermen have long been acquainted with it, affirming reports in Cuba, Puerto Rico, Mexico, and the Caribbean islands. Names such as "sea poisoning," "sea critters," and "ocean itch" have been used as descriptions of this seasonal affliction. A Bahamian old wives' tale specifically warns against ocean swimming between Mother's Day and Father's Day yearly. A local resident from Miami, Florida, described bathing on the beach in the spring of 1903 as the "year we were all poisoned... with some kind of rash which set up an intense itching. It was not so bad for us as we could stay home and doctor ourselves with lotions but the poor men having to work in the fields or hot packing houses were the ones who really suffered." In 1949, Dr. Wiley Sams gave a detailed description of his 12 years of observations and research of "an acute form of dermatitis which occurs within a short time after bathing in the ocean." He recorded the distribution and histology of the lesions, their clinical presentation, and his theory that seabather's eruption was caused by "some living, microscopic organism, in the nature of nematocysts from some form of coelenterate which is free floating."He also cautioned that seabather's eruption should not be confused with "swimmer's itch," a dermatitis involving exposed areas of the body caused by Schistosome cercaride, a free swimming parasitic flatworm found in FRESH water. The term "sea lice" apparently originated during the 1950s and was used by local U.S. residents in describing the condition. This popular term persisted, despite efforts by scientists to discourage use of such an inappropriate designation. Sea lice are actually small parasites that affect fish. Beach goers sought their own remedies for the seasonal itchy rash. Folk remedies included the use of garlic, athletes foot spray, lemon, hydrogen peroxide, witch hazel, rubbing alcohol, spray starch, Epsom salts, and meat tenderizer. Unorthodox attempts to obtain relief included fingernail polish, undiluted bleach, ammonia, gasoline and turpentine. These are especially notable because they were used on extremely sensitive areas of people's bodies. The prevailing term, "sea lice," also encouraged the inappropriate use of head lice medication. When marine biologists at the University of Miami analyzed water samples collected during the periods when complaints of bathers increased, large numbers of cnidarian larvae were noted. Cnidarians are a group of marine animals that contain stinging structures known as nematocysts, and include jellyfish, corals, sea anemones, hydroids, and Portuguese Man o'War. There are more than 9000 species of this group of marine animals; however, it appears that the larval form of Linuche unquiculata, also known as a "thimble jellyfish," is responsible for the outbreaks in South Florida and the Caribbean. This probable causative organism was identified after cultures were successfully grown to maturity from plankton tows collected during 1992 outbreak periods. The suspected organism, barely visible except under excellent lighting, appears like a speck of finely ground pepper. Its size is approximately that of a pinhead floating on the surface layers of the water. The bathing suits worn by swimmers apparently trap variable numbers of larvae, with the fabric acting in a similar fashion to a net.
The many nematocysts surrounding each larva can be triggered to fire by mechanical pressure, such as in the friction areas of a bathing suit or bathing cap, or in body creases. A bather's individual activities may also increase the amount of firing, such as contact with a surfboard, lying on the beach, or sitting on a car seat in the wet bathing suit during the trip home. The surface area of a bathing suit may increase the area over which stings can occur. Female bathers wearing one-piece suits and children and adults wearing T-shirts in the water can increase the risk of a more severe reaction. It is not unusual to see evidence of 200 or more stings under a person's bathing suit. Changes in osmotic pressure may also activate the nematocysis. This could occur from evaporation as the bathing suit dries or from the bather's rinsing with fresh water while wearing the suit. The nematocysts have been noted to have an affinity for hair as well as fiber, which could explain why people have lesions on their necks, from hair dangling in the ocean water and then contacting the skin. The dermatitis usually becomes noticeable between 4 and 24 hours after exposure, although some persons do complain of a "prickling" sensation while still in the water. Persons who have had previous exposure to seabather's eruption, such as lifeguards, tend to have immediate stinging sensations on reexposure. Unfortunately, the only way that beach goers could be warned of the presence of this marine organism in the water was when lifeguards had the dermatitis during their early morning swims. Beach messages specifically warning about "sea lice" have been used since 1989 at access points to public beaches in Palm Beach County. However, no information is available for visitors entering many private beaches owned by hotels and motels. Outbreaks of seabather's eruption appear to be caused by shifts in South Florida's currents, with the highest incidence of cases in such areas as Palm Beach County and Northern Broward County, where the Gulf Stream passes closest to shore. Other areas of coastline are affected by shifts in currents or by strong easterly winds bringing the larvae closer to shore. During initial outbreaks in early spring, adult jellyfish may be seen in the water. It is the larvae, however, not the adult organisms, that are responsible for seabather's eruption. Once the adults die after spawning, the larvae continue to cause the outbreaks, with no mature jellyfish visible as a warning. Lesions associated with seabather's eruption have ranged from a barely discernible macular rash in those with no history of previous exposure to the largely typical maculopapular and occasionally vesicular eruption noted by most. Those with a history of exposure to the organisms have noted urticarial lesions at the onset of reexposure. The dermatitis usually resolves within 1 week, although reactivation of initial lesions has been reported at intervals lasting several weeks or longer. Probably because of the intense itching, many persons report difficultyt in sleeping. Other symptoms include nausea, vomiting, diarrhea, headache, weakcills, muscle spasms, arthralgias, and a sense of malaise. It is unknown whether some of these symptoms reflect the ingestion of infected seawater or are manifestations of a systemic immune response. A retrospective case review of records of persons treated in an emergency department at the geographic center for seabathers eruption noted fever (temperatures greater than 101 degrees F) in 8 of the 57 cases, All 8 cases occurred among children 11years of age or younger. The highest recorded temperature was 103.4 degrees F. TREATMENT: Treatment of this dermatitis currently includes the administration of an antihistamine, such diphenhydramine, for the itching and the application of an over-the-counter 0.5% hydrocortisone cream to the rash areas. Persons suffering from exteneruptions, with or without urticaria, or with recurrences of symptoms may benefit from the administration of epinepherine as well as oral or intramuscular steroids. A prescription for 1.0% corticosteroid cream can also be given. Comfort measures include bathing in a colloidal oatmeal preparation and applying calamine lotion. The latter may be good for children, who benefit from its visual placebo effect. Diphenhydramine and calamine (Caladryl) lotion should not be applied when an oral antihistamine is being used to avoid toxic effects, especially in children. Caution is also in order, to make sure that steroid creams, in combination with oral steroids, are not overused. This may occur when large body surfaces are involved. As noted, children with seabather's eruption tend to exhibit febrile reactions more frequently than adults, probably because of their immune response. Parents should be observant and treat the symptoms. An additional recommendation for children is to clip their fingernails short, to avoid scratching of lesions. Good personal hygiene, especially in the perineal area, will help patients of any age to avoid secondary bacterial infections. Should a secondary infection occur, as evidenced by purulent lesions that are not resolving, follow-up care with a dermatologist is recommended. Any rash needs a thorough evaluation to rule out possible communicable causes. The key to the diagnosis of seabather's eruption is a history of ocean exposure followed by the development of a dermatitis within 24 hours of exposure. Multiple persons within one household are typically affected. Persons with the rash of seabather's eruption are not considered contagious.
PREVENTION: Outbreaks of seabather's eruption occur intermittently between March and August, but they appear to peak during early April through early July. There have been many days when no infestations have occurred. Beach goers need to listen to local beach reports and observe daily posted beach messages in affected areas. The following recommendations may also help in minimizing the number of stings:
1. Each beach goer needs to assess his or her individual risk of an immune response. Persons with a history of a severe reaction should confine their beach activities to land, or use pool facilities instead, during outbreaks.
2. Swimmers should avoid wearing T-shirts while in the ocean. Use of a topical sunscreen and limiting sun exposure protects against solar injury. There is some evidence that use of a topical sunscreen or suntan lotion may actually protect skin from penetration by the nematocysts.
3. Women should consider two-piece instead of one-piece bathing suits, to reduce the surface area of swimwear that could trap larvae. It is possible that smooth, tight weave bathing suits may trap fewer larvae than suits with an open-weave fabric.
4. After ocean exposure, swimmers need to change out of their bathing suits as soon as possible after exiting from the water. Most lesions have occurred from contact with contaminated swimwear. Removal of possibly contaminated swimwear, followed by a shower to rinse off loose larvae, should limit the number of stings. If showers are in a public area, it is suggested that people bring a second suit to the beach; after removing the first, possibly contaminated suit, they can don the second suit and then shower. Showering with fresh water while still wearing a contaminated bathing suit could cause discharge of nematocysts trapped in the fabric of the suit.
5. Bathing suits should be thoroughly washed with detergent and heat-dried after use. Some have experienced a recurrence of symptoms when wearing suits that had only been air-dried. Air-dried nematocysts still have the potential to fire. A person who has had a severe reaction may be wise to discard the infested suit. Now that research of seabather's eruption has begun, information to protect the public will be distributed as it becomes available.
1. Sea lice survey. Boca Raton, Florida: Boca Raton Community Hospital. 1992.
2. Lauther OC. The lonesome road. Miami: Center Printinq, 1963:91-2.
3. Sams WM. Seabather's eruption. Arch Dermatol 1949:60:227-37.
4. Black NA, Szmant AM. Larval thimble jellyfish (Linuche unqui culata) as a possible cause of seabather's eruption. Presented at 1992 Symposium on Flonda Keys Regional Ecosystem. Miami, Nov 18, 1992.
5. Thorinqton GU, Hessinqer DA. Control of discharqe: factors affecting discharqe of crudes. In: Hessinqer DA. Lenhoff HM. eds. The biology of nematocysts. San Dieqo: Academic Press. 1955:232-53.
6. Retrospective case review/medical records of SBE cases from 4/92-7/92. Boca Raton, Florida: Boca Raton Community Hospital, 1992.
7. Heeger T, Moller H, Mrowietz U. Protection of human skin against jellyfish (Cyanea capillata) stinqs. Marine Biol 1992:113:669-78.
© Mary T. Russell, 1995 email@example.com
Wash the car. Wash the windows. Wash the floor. What are you doing to that poor sponge anyway? Poor sponge? That washing aid you’re using, if your lucky enough to have a true sponge, is all thats left of a marine animal.
Sponges are strange creatures and not at all like most of the animals with which we are familiar. They can be almost any color, from white to gray to any shade of red or yellow to purple and black. They have no head, body, arms, legs or any other obvious structures that we generally associate with animals. Some sponges live singly. Others live in crowded colonies that form crust like layers over rock surfaces. Individual sponges can be as small as a centimeter or as large as two meters across. Our washing sponge certainly doesn’t look alive. In fact, it isn’t. The “sponge” that most of us think about when we hear the word is really only the skeleton of a sponge animal. The skeleton of a living sponge would be surrounded with cells. the body plan of a sponge is simple. Sponges are considered to have the lowest multicellular organization of all animals. This distinction elevates sponges to just one step above the one celled protozoans.
When examining a living sponge, a close look reveals that the sponge is covered with many small holes or incurrent pores . The pores explain the name of the phylum to which sponges belong, Porifera , which means “pore bearing”. We also see a larger opening called the osculum (Latin for “little mouth”). If we were to place a drop of food coloring near the sponge, we would be able to follow the dye as it moved into the incurrent pores and out the osculum.
The colored water is moved through the sponge by the movement of whip-like structures (flagella) found on the cells that line the inside of the sponge’s body. These cells are shaped somewhat like a goblet and are called collar cells or choanocytes. The current caused by these collar cells moves not only water but also plankton and other small bits of organic matter the sponges use for food. The current also helps supply oxygen to the living cells. Through water movement, the sponge draws its food and oxygen to itself. Moving the environment through the sponge keeps the sponge from having to move through the environment. The adult sponge, therefore, can and does spend its life permanently attached by its base to a rock or shell or some similar substrate. The sponge is sessile, or relatively non-moving. (Q1 & 2).
A simple sponge has a hollow body, and the body wall is formed of two layers of cells separated by a layer of jelly-like material. The outer layer or epidermis protects the sponge. The inner layer contains the collar cells. The jelly layer is a mixture of loose cells, spicules and/or spongin. The spicules are noncellular skeletal structures that help support the sponge’s body. Spongin is a tough, fibrous protein material that also helps to support the sponge. (Q3)
Spicules are secreted by living cells. They are small rods composed of either lime (calcium carbonate) or glass (silica). The spicules come in a variety of shapes and sizes. Each species of sponge has its own special combination of spicules. Like a fingerprint, these combinations may be used to identify the species of sponge.
Biologists have divided spicules into four basic shapes:
1. single axis or straight spicule (monoaxon)
2. three pronged or multiple of three spicule (triaxon)
3. four pronged spicule (tetraxon)
4. many pronged spicule (polyaxon) (Q4)
Spicules are secreted in many sponges by small amoeba-like cells called amoebocytes . These amoebocytes also distribute digested food and oxygen to other cells as they wander through the jelly-like layer. Often sponges produce two types of spicules. The large spicules are called megascleres and the smaller spicules of a different design are called microscleres.
Jellyfish, sea anemones, corals and microscopic hydroids are very different animals, yet all grouped together in the phylum Cnidaria . What do these animals share that cause biologists to group them within a single phylum?
The Cnidarians are tentacle-bearing, radially symmetrical animals with a sac-like body composed of two basic cell layers. Radial symmetry is a body design in which parts radiate from a center as spokes radiate from the hub of a wheel. The saclike body provides an internal space for digestion (the gastrovascular cavity ). The hollow space opens to the outside at one end to form a mouth. The presence of a mouth and digestive cavity permits the use of a much greater range of food sizes than is possible in the sponges.
Cnidarians represent an important advance in cellular organization. The protozoa and sponges operate on the cellular level, Cnidarians are at the tissue level of organization. The different kinds of cells present are organized into groups in which all cells have similar structural and functional characteristics. A tissue is a group of similar cells organized to perform a particular function. Cnidarians have specialized epidermal, nervous, digestive and muscular tissues.
Two body forms are found among the members of the Cnidarians:
a. Medussa- an umbrella shaped jellyfish form with trailing tentacles
b. Polyp-a cylindrical body, attached at the base, with tentacles at the upper margin encircling the mouth. (Q5)
The two body forms of the Cnidarians are grouped into three classes:
Class Hydrozoa - the hydroids
Class Scyphozoa - true jellyfish
Class Anthozoa - the sea anemones and corals (Q6)
The class Hydrozoa contains a large number of common Cnidarians. Because of their small size and excellent camouflage, most people are unaware of the members of this group. Most of the life cycle of the hydrozoans is spent in the polyp stage. Most marine hydrozoans are colonial , a great many individuals are associated on the same tree-like stalk.
Members of the class Scyphozoa spend most of their lives in the free-floating medusa form. The jellyfish is found in seas from the Arctic to the tropics. These fragile looking umbrellas are able to withstand long sea journeys and much wave battering. The term medusa has its origin in ancient Greece. The Gorgon Medusa of Greek mythology was a woman-monster figure that, instead of hair, has a mass of waving snakes atop her head. The resemblance of the Medusa and the half-round jellyfish, with tentacles streaming snake-like from its edges is very evident.
All of the members of the class Anthozoa spend their lives as attached polyps. Most anthozoans found i n Northwest waters are much larger than are the Hydrozoa polyps. If the polyp is large enough to be easily seen with the naked eye, it is probably an anthozoan. This class includes the coral animals which are found in all seas. Anthozoans have adopted many different forms.
Cnidarians show many different life cycles. The life cycle of a jellyfish can be used to show the general features of the cnidarian life cycle.
Jellyfish go through three stages of development: larval, polyp, and medusa (mature jellyfish). In most jellyfish, sexes are separate. The gonads, or primary sex glands, whether male or female, develop in the lining of the gastrovascular cavity. When spawning occurs, the eggs or sperm are released to the outside through the gastrovascular cavity. The eggs generally settle on the oral arms and are fertilized there. Young embryos begin their development on these long arms. They then detach and become microscopic larvae covered with hair-like cilia. The rapid beating of these cilia propel the larva through the water.
After leaving the protection of the adult, the larva tries to find a home where it can attach and begin the second stage of development (polyp). Rocks, shells, cans or bottles in shallow protected water are all suitable materials, but jellyfish larvae seem to prefer oyster and clam shells.
Once the larva has found a home, it begins the polyp stage. First, (during the scyphistoma period), the body divides into segments: Each segment then develops until it is pinched off as a ephyra larva. This pinching off is called strobilation.
Ephyre larvae grow to adults and are called medusae. At this third and final stage of development, they are ready to produce eggs and sperm and begin the life cycle again. A jellyfish will normally live three to six months: rarely does its life span exceed a year.
Cnidarians possess special structures, the nematocysts or stinging cells, which aid them in obtaining food. These stinging structures are actually organelles of a cell known as a cnidoblast (nid-o-blast). Cnidoblasts differ from species to species. They perform their food-getting or defensive functions in one of three ways:
a. volvents-wrap around and ensnare the victim
b. penetrants-stick into the victim, like a harpoon or arrow
c. gllutinants-not only penetrate the victim, but inject a poison.
Some biologists consider cnidoblasts to be the most specialized cells in the animal kingdom.
Cnidoblasts are rounded cells with the nucleus near the base. One end of the cell contains a short, bristle-like process called a cnidocil. The cnidocil acts like a trigger and is usually exposed at the surface. The interior of the cell is filled by a capsule containing a coiled, pleated tube. The end of the capsule which is directed outward is covered by a cap or lid.
The firing mechanism is not well understood. It appears that chemical changes occur in the cell membrane that cause an inrushing of water and greatly increased pressure. As a result, the lid is forced open, the tube turns inside out, and the entire nematocyst explodes to the outside.
RealSurf's SurfHealth Pages
Bluebottles, the scourge of summer
In early February 2000, bluebottles hit the beaches of Sydney in plague proportions. And the email horror stories started arriving at RealSurf. So, we did the logical thing. We asked folks for their favourite bluebottle sting treatments.
We've divided these into two categories: the official and the folk. Official recommendations come from either medical professionals or from the Surf Life Saving movement. And the folk category overlaps the official and encompasses everything else.
OFFICIAL BLUEBOTTLE (Man-of-War)TREATMENT RECOMMENDATIONS
The Bluebottle or Portuguese Man-of-war inhabits (and at times infests), with seasonal variation, the warmer seas of the world. Each bluebottle is actually a small colony of creatures that all perform different, complementary roles. The gas filled body is one single animal- the float. Half of them have sails oriented one way and half at ninety degrees- so they sail in different directions and spread out further. Smaller organisms are responsible for reproduction and the most evil ones, the nematocysts, make up the small tentacles on the float and the long tentacle (up to ten metres long). These tentacles carry the venom and cause the stings. They are actually used to paralyse and trap small fish, which these wretched creatures eat to survive. When the wind blows onshore, they can appear at beaches in large numbers, stinging local heroes and kooks indiscriminately.
As a doctor in Accident and Emergency in a hospital close to the beach, I see loads of bluey stings in summer. Over the years, various remedies have been advocated eg rubbing sand on a sting, which pushes the venom deeper into the skin and makes it worse; ice, which does decrease the swelling and inflammation but doesn't destroy the toxin; vinegar, which as a weak acid has a mild effect on neutralising the toxin but doesn't work that well; and Stingose, which according to one text I consulted is pretty useless.
The current recommended treatment is to put the sting in hot water, preferably in a shower, as hot as you can stand for at least fifteen minutes. The heat denatures the toxins. I've tried it myself and reckon it works pretty well, but by the time you get to the shower you will probably already have a few welts. Ice is good for these, scratching is bad and moisturiser (or hydrocortisone cream) is soothing. Anti-histamines can largely relieve the itch eg Telfast, which you can buy at the chemist (follow the directions.) At night a sedating antihistamine like Phenergan can help you sleep and relieve the itch.
With a bad sting, the venom can cause nausea and joint pain. If it gets into the lymphatic system, it can cause excruciating pain in the lymph nodes eg in the groin if stung on the leg. This doesn't usually last more than an hour or two and simple analgesics like panadeine or panadol are usually effective. This pain can be almost overwhelming.
Lastly, although I have never seen a case, anaphyllaxis can occur ie system shut down due to severe allergic reaction- low blood pressure, rapid pulse and breathing difficulty. This requires emergency treatment in hospital or from the ambos with hydrocortisone, antihistamines and sometimes adrenaline(or epinephrine if you are from Don's homeland)…every minute is crucial when this occurs. Breathing trouble is more likely in asthmatics, children and people known to be allergic to blue-bottle venom. Any sign of chest tightness or breathing trouble is a good reason to get to hospital immediately. There have been recorded cases of death from Portuguese Man-of-war stings, though as far I am aware, there have been none in Australia.
It's hard to say anything positive about these hateful creatures, but when the nor'easter is howling on your one afternoon off for the month and you have to paddle out anyway, wear a long rashy or a steamer or be prepared to suffer. They are after all only trying to catch some fish…
1. Dangerous Marine Creatures Dr Carl Edmonds Copyright 1989 Reed Books Pty. Ltd.
Venomous Creatures of
3. The ER
4. Thousands of hours in the water
Official SLSA treatment: Remove all stingers IceStingose Previous years Vinegar (not something you normally have at the beach).
Spongy landscapes name..................................................................pd...............
1. What kind of symmetry do sponges have? (Name 2)
2. A) What is the name of the incurrent waterway?
B) What is the name of the excurrent waterway?
3. What is a wandering amebocyte?
4. What animals are found around sponges?
1. What are the characteristics of a jellyfish?
2. What is a nematocyst?
3. How do adult jellyfish (medusae) move from one place to another?
4. What direction can adult jellyfish (medusae) move on their own?
5. What do jellyfish eat?
6. How are jellyfish useful to man?
7. How is a sea nettle different from a jellyfish?
8. How is a moon jelly different from a jellyfish?
9. What phyla do comb jellys belong?
10. (A)How are comb jellys different than jellyfish?
(B) How are comb jellys similar to jellyfish?
11. What does luminescent mean?
12. How is the sea walnut harmful to sea life?
13. How dangerous are jellyfish and what should you do if stung?
14. Is pollution causing an increase in the abundance of jellyfish?
15. What other problems can jellyish cause?
Killer Down Under Name....................................pd...........
1. How many people have died in the last century from the BOX jelly stings? (A) 30 (B) 60 (C) 65 (D)4
2. How quickly can cube (box) jelly venom kill a human? (A) several hours (B) 4 minutes or less (C) an hour (D) it doesn't kill
3. How does the venom affect the heart? (A) speeds it up (B) only effects nerve cells not heart (C) slows it down and stops it
4. What is the difference between a planulae and a polyp? (A) planula are mobile and polyps are attached (B) planula are attached and polyps are mobile (C) polyps are adults and planula are larva
5. Where were Chironex medusa found in the wild? (A) close to the mainland (B) in estuaries and streams (C) up to 40 miles offshore (D) a and b are correct (E) b and c are correct.
6. How long does it take for a box jelly to undergo metamorphosis? (A) 12 days (B) 24 days (C) 6 years (D) 4 hours
7. What causes the stinging cells to be triggered? (A) stimulated by temperature changes (B) stimulated by touch only (C) stimulated by chemicals (D) b and c are correct
9. What is a pedalium? (A) tentacles (B) mouth part (C) feeding appendage (D) a live shrimp fed to cube jellies
10. What feeds off box jellies? (A) Asian fishermen (B) sea turtles (C) Great White Sharks (D) Sea Snakes
Darken in the correct answer
1. |A| |B| |C| |D| |E| 2. |A| |B| |C| |D| |E|
3 |A| |B| |C| |D| |E| 4. |A| |B| |C| |D| |E|
5. |A| |B| |C| |D| |E| 6. |A| |B| |C| |D| |E|
7. |A| |B| |C| |D| |E| 8. |A| |B| |C| |D| |E|
9. |A| |B| |C| |D| |E| 10. |A| |B| |C| |D| |E|
QUESTIONS SEA LICE
1. During what time of year does this occur?
2. Which part of the body do the rashes occur?
3. What were some of the names of these rashes?
4. What 2 facts did Dr. Wiley Sams come up with?
5. What are sea lice?
6. What did the water samples taken show?
What causes the outbreaks in
8. Why are the highest incidence of cases in
9. What causes the outbreaks?
10. What are some of the symptoms?
11. How are the rashes treated?
12. Why is this worse in children than adults?
13. Is the rash contagious?
14. List 4 ways to avoid this problem.
QUESTION S WITH RUB-A-DUB
1. How is water moved through the sponge?
2. What adaptations (special structures or behavior) allow the sponge to lead a sessile existence?
3. From the outside in, what structures comprise the body wall of the sponge?
4. Name the 4 types of spicules and how they would be useful to biologists?
5. What are the two body forms found among cnidarians? Describe each
6. Name the 3 classes of cnidarians and give an example of each.
7. What are the three types of nematocysts and how does each type function?
Get your answers for the following from the STING reading.
Jellyfish, sea anemones , corals are all interesting animals. Jellyfish come in a great variety of sizes and color. From microscopic, clear specimens to the Portuguese Man of War with tentacles several meters in length, all of the jelly fish are
__ __ __ __ __ __ __ __ __ __ __
9 11 6 7 4 5 3 8 2 1 10
To learn what this word is, 1. from the following list of words, select the one that best fit each definition below and write it in the spaces at the left. Start with the first space and don’t worry if it doesn’t go all the way across. Transfer the circled letters to the spaces above.
words: medusa penetrants scyphozoa volvents tissue hydrozoa anthozoa Cnidaria larval cnidoblast nematocysts sacklike radial polyp tentacle cilia
__ __ __ __ 0 __ __ __ __ __ __ __ 1. Sea anemone belongs to this class of cnidarians.
__ __ __ __ __ __ __ __ __ 0 __ __ 2. These specialized cells contain the nematocysts.
__ 0 __ __ __ __ __ __ __ __ __ __ 3. Members of this phylum are tentacle bearing radially symmetrical animals which posses stinging cells.
0 __ __ __ __ __ __ __ __ __ __ __ 4. During this stage, the jellyfish is microscopic and covered with cilia.
__ __ __ __ __ 0 __ __ __ __ __ __ 5. This umbrella shaped form found among the cnidarians takes its name from Greek Mythology.
__ __ __ __ __ 0 __ __ __ __ __ __ 6. These specialized structures are used to harpoon, ensnare or poison.
0 __ __ __ __ __ __ __ __ __ __ __ 7. A cylindrical body form, attached at the base, with tentacles encircling the mouth
__ __ __ 0 __ __ __ __ __ __ __ __ 8. The presence of this kind of body allows the cnidarians to use a much greater range of food sizes than is possible in the sponge.
__ __ __ __ __ __ 0 __ __ __ __ __ 9. Jellyfish belong to this class of cnidarians.
__ __ 0 __ __ __ __ __ __ __ __ __ 10. These projections are found on all cnidarians.
__ 0 __ __ __ __ __ __ __ __ __ __ 11. Cnidoblasts of this variety wrap around and ensnare the victim.
15. rubadubquest cwks hd