come away with no more than painful red welts. The 

 real danger is pain or cramps so severe as to cause 

 panic and prevent one from reaching shore, and this 

 is especially true of encounters with one of the most 

 dangerous coelenterates of all, the floating colony 

 called the Portuguese man-of-war. 



Isolated instances of the use of stinging capsules 

 in certain species of flatworms and nudibranch 

 moUusks have ceased to puzzle zoologists, since it 

 has been shown that these are always obtained by 

 feeding on coelenterates and then manipulating the 

 captured capsules into positions on the surface where 

 they can be used in the same manner as in the ani- 

 mals that produced them. 



Coelenterates on the whole show little promise as 

 a direct source of food for man. Sea anemones have 

 long been eaten in France, Italy, and Greece, and in 

 some of the Pacific islands. As late as the nineteenth 

 century they were regularly sold in Mediterranean 

 markets and brought a good price in Bordeaux. Some 

 of the green anemones were especially popular, and 

 after being boiled in sea water were said to acquire a 

 firm and palatable consistency, excellent with any 

 sauce. Wrote one early naturalist gourmet, "They 

 are of an inviting appearance, of a light shivering 

 texture, and of a soft white and reddish hue. Their 

 smell is not unlike that of a warm crab or lobster." 

 Some cooks prepared anemones as they would oys- 

 ters, and often served the two together. Dahlia anem- 

 ones are still eaten on the Continent but in England 

 they are used only as bait with long fishing lines. 



Certain jellyfishes are regularly eaten in Korea, 

 Japan, and China. When these turn up in large shoals 

 they are dried and cut into strips, which can be re- 

 constituted with water whenever desired. The chief 

 contribution of jellyfishes to the human diet, how- 

 ever, is indirect and is appreciated only by fisheries 

 experts. Certain species of jellyfishes, says L. A. 

 Walford in Living Resources of the Sea, are among 

 the most valuable marine animals from man's view- 

 point because they provide portable shelter for the 

 young of commercially valuable fishes such as hake, 

 haddock, cod, horse mackerel, and butterfish. The 

 young fishes accompany their host in the floating sur- 

 face plankton, feeding around it within a radius of 

 several feet and darting quickly to safe harbor be- 

 neath its spreading umbrella whenever danger threat- 

 ens. The relationship may even be an essential stage 

 in the life cycle of some fishes, and the fingerling that 

 fails to find a jellyfish host within a certain time may 

 not long survive among the hungry predators of the 

 sea. This is not to deny that some jellyfishes take a 

 great toll of the juvenile fish population. 



Red corals are fished from Italian and other 

 Mediterranean coasts, and also in Japan, for manu- 

 facture into jewelry and various ornaments. Dried 

 sea fans, sea whips, sea feathers, and especially 



A common traclnline jellyfish of shore waters is Goni- 

 onemtis vertens, shown here swimming actively. ( Eng- 

 land. D. P. Wilson) 



dried and bleached coral skeletons, all of them highly 

 decorative, are sold in the same shops that sell many 

 tons of mollusk shells every year. Even the delicate, 

 horny skeletons of sheathed hydroids have some 

 economic value. In England, centering in the Thames 

 estuary, there is a small "whiteweed industry." Boats 

 drag iron rakes over shell-and-sand bottoms, pulling 

 up feathery colonies of Serliilaria argentea. some- 

 times other species or other genera. The processed 

 hydroid plumes are dyed green or other colors and 

 sold for decorative purposes, mainly in the United 

 States, as "ever living house plants" or as "sea 

 ferns." 



Parasitism by coelenterates is rare, though even 

 hydroids can parasitize fish; but the group as a whole 

 has a notable talent for sitting down uninvited at the 

 table of other invertebrates, or for living associated 

 with snails, crabs, and a great variety of other crea- 

 tures in a relationship which may possibly be of some 

 benefit to the host as well as to the coelenterate 

 guest. Playing the role of host, on the other hand, are 

 the many jellyfishes and large tropical anemones 

 that shelter fishes, all the large attached coelenterates 

 that provide a place for myriads of tiny invertebrates 

 to hang onto in a restless ocean, the coral crevices 

 that shelter hundreds of kinds of fishes and crabs and 

 worms, and — most important of all — the widespread 

 mutualistic ties of coelenterates with green or yel- 

 lowish brown algal cells. Certain hydras of fresh wa- 



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