ACTINIADJS. 



483 



Actinia, under the names of A. troglodytes (the Cave- 

 dweller), A. viduata, and A. Anguicoma (the Snaky- 

 locked). Mr. Gosse, in his Devonshire Coast, makes A. 

 viduata synonymous with A. anguicoma; and gives a 

 drawing and a description of an anemone which he calls 

 anguicoma, and which closely resembles undoubted 

 specimens of Johnston's A. troglodytes. Many objections 

 might be taken to Mr. Gosse's description of species, which 

 he makes out from the number of their tentacles, although 

 found in company with each other, and, as he justly re- 

 marks, are of " the same size and form." 



Of the voracity of the actinia many remarkable state- 

 ments have been made known; it may nevertheless be 

 kept in the aquarium for many months, if supplied with 



1 2 



Fig. 235. 



1, Actinia rubra Sea marigold, near which is one shown retracted. 2, Actinia 

 bellis, Daisy sea-anemone (side view). 



water containing particles of organic matter. Although 

 the several structures of actinia admit of being resolved 

 into two foundation membranes, an ectoderm and an en- 

 doderm, yet each of these, more especially the former, 

 manifests a tendency to differentiate into secondary layers, 

 so that several apparently distinct tissiies are recognisable 

 in the body of the fully-formed animal. Both membranes 

 hava their free surfaces more or less covered with cilia 



n2 



