81 



probably be considered a variety of the Actinia gemmacea, 

 as that kind is liable to so many variations, but it had not 

 the appearance of belonging to that species. The favourite 

 site for them is on the claw of the Corwich crab, (M. 

 verrucosa) and on the Pinna ingens. 



ANTIIEA. Johnston. 

 Generic Character : Body cylindraceous, adhering by a broad 

 base; tentacula disposed in circles round the mouth, 

 elongated, tapered, and incapable of being retracted 

 within the body. Johnston. 



SEA-TORCH THISTLE. A. Cereus. Body smooth, 

 cylindrical, longitudinally furrowed, ending superiorly in 

 a waved line; tentacula long and generally tipped with 

 red. PI. xiv., fig. 2. 



Actinia cereus, Ellis and Solander's Zooph., p. 2, no. 1. 

 Turton's Lin., vol. 4, p. 103. Actinia sulcata, Stewart's 

 Elem., vol. 1, p. 394. Fleming's Brit. An., p. 498. Pen- 

 nant's Brit. Zool., vol. 4, p. Hydra cereus, Stewart's Elem., 

 vol. 2, p. 451. Anthea cereus, Johnston's Brit. Zooph., 

 p. 22 L. 



Hah. In the crevices of the rocks ; Polperro, Talland 

 sand, Looe, Fovvey ; common. 



This species is very common on all that part of the south 

 coast that has been examined, as much, if not more so than 

 the Sea Anemone, A. Mesembryanthemum, but as it is gre- 

 garious and confined to pools and crevices of rocks which 

 always remain covered with the sea, and of a light colour, 

 it is not so readily observed as that species which lies in- 

 discriminately scattered over the rocks between tide marks. 

 The pools they prefer are those which have a southern aspect 

 and which are visited by the sea at every tide. Sometimes 

 they occur only in small companies, and at others singly, 

 according to the nature of the spot, but I have frequently 

 found them covering a surface of three feet in diameter. 

 The animals are generally in close approximation with each 

 other, and most commonly in contact. They are liable to so 

 many changes of form that a minute description of them 

 would be both tedious and useless. In a contracted state, 

 they are generally columnar and of equal diameter through- 

 out, and the tentacula diminished both in size and length ; 

 sometimes they are hemispherical, with the tentacula pressed 

 together and protruding from a central orifice ; at others 

 the body is drawn towards the base and flat, while the 

 oral surface is exposed or covered only by the contracted ten- 

 tacula. The surface of the body is smooth, but longitudinally 

 striated ; the furrows run from the base to tho margin of 

 the oral disc, where they terminate in a waved or festooned 



