ican Atlantic coast it is one of the largest and most 

 familiar anemones from Labrador to New Jersey 

 (Plate 22). On the Pacific coast it extends along the 

 shallow shore from Alaska to Monterey, California. 

 As far south as La Jolla it has been seen on the rims 

 of underwater canyons by skin-diving, aqualung- 

 equipped biologists, like Conrad Limbaugh of the 

 Scripps Oceanographic Institute, who are learning to 

 know the anemones and other invertebrates of deeper 

 shore waters as we now know those of tide pools. 

 In the Bay of Morlaix, in Brittany, where perhaps 

 a third of the bay is difficult or impossible to dredge, 

 Pierre Drach, of the Biological Station at nearby 

 Roscoff, is diving with open rubber suit and aqua- 

 lung on the steep rocky slopes. To the study of such 

 slopes he is bringing the same careful methods of ob- 

 servation that we use so much more easily on land 

 for studying exactly how animals are associated with 

 each other. This is something we cannot learn from 

 the jumbled masses brought up by the dredge from 

 Hat bottoms. 



Favoring deeper waters and northern seas, around 

 the globe, is the dahlia anemone, Tecilia, which is 

 large and stout and has short, somewhat blunt tenta- 

 cles that taper from wide bases. In the variety of 

 Tecilia jeliiui that is common on northern European 

 shores the column is often red spotted with green, 

 and the tentacles are strongly banded with reds, 

 blues, grays, and olives. The deep-water variety, 

 with a disk 1 foot or more across, is less strongly 

 marked and likely to be buff, yellow, or orange. On 

 American coasts the dahlia anemones are similarly 

 bright red, and often also pink, and in Maine one 

 has been called the thick-petaled rose anemone. 

 They are common below low-tide mark as far south 

 as Cape Cod on the Adantic coast, and southward 

 to California on the Pacific coast (Plates 17 and 20). 



Rocky bottom is the favored substrate of anemo- 

 nes, and in protected areas every crevice is jammed, 

 every tide pool carpeted, with anemones crowded 

 disk to disk. Some burrow in sand or mud, then lie 

 with the long, slender column completely buried and 

 only the feeding disk outspread on the surface, as 

 Peachia and Milne-Echvanisia on European shores, 

 Edwardsia in New England, Edwardsiella and Hare- 

 nactis on the southern California coast. Many anem- 

 ones hang from wharf pilings or floating wood, cling 

 to seaweeds or eelgrass, or attach to shells and stalks 

 of sessile animals, especially if on soft bottoms. Oth- 

 ers lead a mobile life affixed to jellyfishes and comb 

 jellies, the backs of crabs, the shells of living marine 

 snails, or the snail shells appropriated by hermit 

 crabs. 



The classical alliance between anemone and her- 

 mit crab is that of Adamsia palliala on the hermit 

 crab Eupagurus prideauxi in European waters. The 

 crab seeks out a young anemone and holds it until it 



A group ol plumose anemones, Melridiiim. from north- 

 ern European waters. Some are expanded, spreading 

 their great lobed and frilled disks. Two are con- 

 tracted; the large one in the background, which has 

 pulled in its disk, resembles a plump tomato. (Giinter 

 SenfFt) 



attaches to the shell just below the mouth parts of 

 the crab. As the anemone grows, the base of its col- 

 umn extends upward in two lobes that meet and fuse, 

 embracing the shell. The anemone secretes a horny 

 membrane that roofs over any holes in the shell and 

 extends beyond the shell margin, enlarging its ca- 

 pacity and so minimizing the number of times the 

 growing crab must change houses. When it does 

 move to a new shell, the crab transfers its associate, 

 which submits readily instead of clinging stubbornly 

 to the old shell as it does if we try to remove it. The 

 anemone receives scraps of food from the crab's less- 

 than-neat feeding, and the crab is protected by the 

 stinging tentacles and also by the stinging filaments 

 of the anemone. These last are long filaments that 

 extend freely in the digestive cavity from the swollen 

 glandular edges of the internal partitions. They are 

 richly endowed with stinging capsules, and when the 



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