anemone contracts they are extruded through the 

 mouth and through special holes in the body wall, 

 the cinclides. Many anemones, including Meiridiiim, 

 extrude stinging filaments; but it is interesting that al- 

 most all the anemones that live on hermit crabs do 

 have them. Adamsia palliata apparently cannot live 

 without its crab host, but other anemones so associ- 

 ated are less dependent. Calliactis parasitica lives 

 on Eupagurus bernhardus ( Plate 1 5 ) in Europe, and 

 Calliactis tricolor on hermit crabs along the Ameri- 

 can southeast coast and in the Gulf of Mexico. 

 Other species of Calliactis and other anemones, 

 however, are reported to have similar habits in all 

 parts of the world, mostly in fairly warm waters, as 

 of the Gulf of California, Chile, Hawaii, Japan, the 

 Indo-Pacific, the Great Barrier Reef, East and South 

 Africa. In the tropics certain reef crabs go about 

 brandishing an anemone in each claw, presumably 

 as defensive and food-catching devices, for the crabs 

 are said to reach up and take food from the disks of 

 the anemones. 



Apparently contented anemones have been ob- 

 served to hug the same crevice for more than thirty 

 years. Others move occasionally, especially if their 

 posts turn out to be too surfy or on the sunny side; 

 and the more restless species walk about frequently 

 by a slow kind of muscular gliding. The minyads, 

 mentioned earlier, have the basal disk expanded into 

 a rounded float. The tiny Gonactinia was mentioned 

 earlier as one of the few anemones that can swim by 

 stroking the water with its tentacles. Undulating the 

 whole body produces brief swimming excursions for 

 some bigger forms, and Stomphia coccinea in Puget 

 Sound frees itself and swims about by muscular un- 

 dulations whenever it is touched by certain starfishes. 

 This may be a rapid-escape mechanism, as at least 

 one of the starfishes involved has been seen to feed 

 on anemones. For the most part, however, sea anem- 

 ones have few predators besides those intrepid eaters 

 — sea slugs and men. 



Anemones expand their column and tentacles 

 by taking in water, and they are very vulnerable to 

 drying. Most live below low-tide mark where they 

 never have to face this problem, but shore anemo- 

 nes usually pull in their tentacles and contract until 

 the tide returns. The beadlet anemone. Actinia 

 equina, of European waters, is bright red with a row 

 of blue beads around the column just below the ten- 

 tacles, but it occurs also in less common brown and 

 green varieties. At Helgoland in the North Sea red 

 and green Actinias literally carpet the rocks. On 

 British and French shores one sees them on exposed 

 spots where others cannot brave the surf and at high 

 shore levels where more delicate anemones could not 

 survive the long intervals of dryness. As the tide ebbs 

 the beadlet contracts into a formless blob of red jelly 



that in hot weather dries to a leathery knob before 

 the water comes surging back to restore its elegant 

 form, translucent coloring, and delicate texture. Ac- 

 tinias are the commonest of British shore anemones, 

 and their habits of feeding on jellyfishes, small fishes, 

 and other sizable prey are known to few people as to 

 Douglas and Alison Wilson. They were surprised one 

 day, however, to come upon a unique sight — a rocky 

 ridge in a Devon bay that at low tide was covered 

 with beadlets, each with a long, silvery sand eel 

 protruding from its mouth. A shoal of fishes had run 

 into the ridge, and there were the anemones, each 

 striving to cope with prey much too long to be swal- 

 lowed, while other animals were managing bites of 

 the protruding bodies. 



Suddenly contracting anemones often eject water 

 from the mouth or through special holes in the body 

 wall. At low tide one sees jets of water issuing un- 

 expectedly from closing anemones, and hears the 

 squshing sounds made by luckless ones that have 

 been stepped on. Kneel beside a tide pool and poke 

 almost any anemone, and it will hug your finger as 

 the discharge of stinging threads makes the tentacles 

 cling and as the folding disk pulls in. Then, as in a 

 string pouch being closed by a tightening of the cord, 

 the anemone may contract a ring of circular muscle 

 around the opening and leave your intruding finger 

 outside. One of the few anemones that does not close 

 up and that rarely retracts its tentacles is the "opelet" 

 or "snakelocks," Anemonia sulcata, a dull green or 

 pinkish brown anemone common on European shores 

 (Plate 14). In the sunny spots shunned by most 

 anemones, it spreads its long, snaky tentacles, often 

 tipped with mauve, where they best display to the 

 light the green algal cells within the tissues. Perhaps 

 it has little need to retreat, for its stinging capsules 

 are especially large and numerous and it is often 

 something of a feat to disentangle the clinging tenta- 

 cles from one's fingers. Also green with contained 

 algal cells are the two common anemones of the 

 American Pacific coast, the solitary "big green 

 anemone," Anthopleura xanthogrammica, and the 

 "aggregated anemone," Anthopleura elegantissima 

 (Plate 13). Like the snakelocks, they feed in full 

 light. When darkness comes and most other anem- 

 ones begin to unfold their disks and feed, the an- 

 thopleuras draw in their tentacles and rest. 



The big green anemone is known from Japan, the 

 North Pacific, and down the American Pacific coast 

 from Alaska to Panama in the very low tide zone or 

 in well-aerated tide pools. Flourishing specimens 

 growing in brilliant sunlight are a beautiful emerald 

 green, often marked with purple, and as much as 10 

 or even 16 inches across. In spite of their large size, 

 their sting causes only a slight tingling. Under 

 wharves, in caves, or in shaded spots they are pale 



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