COKALS AND CORAL MAKERS. 7 



Pacific, a coloured figure of which is given in the Atlas of the 

 Author's Report on Zoophytes (Plate HI.)? had a diameter 

 across its disk o( four tee? i inches ; and it was also one of the 

 most beautiful in those seas, having multitudes of tentacles 

 with carmine tips and yellowish bases, around the open centre, 

 gathered into a number of large groups or lobes. 



With rare exceptions. Actiniae live attached to stones, shells, 

 or the sea bottom, or are buried at base in the sand or mud. 

 The attached species have the power of locomotion, through 

 the muscles of the base, but only with extreme slowness. The 

 loose stones on a sea-shore near low tide level often have 

 Actiniae fixed to their under surface. A very few species swim 

 or float at large in the ocean. 



CAXCRISOCIA EXPANSA St., ON THE BACK OF DORII'I'E FACCHINO. 



Now and then an Actinia puts itself on the back of a crab, 

 and thus secures rapid locomotion, but only at the will of the 

 crab, which may at times give it some hard rubs : — a kind of 

 association styled cotnmensalisju by Van Beneden, as the two 

 in a sense live at the same table, without preying one upon 

 the other. In the above example, from the China seas, the 

 Actinia has mounted a Dorippe. The figure is from the 

 Proceedings of the Essex Institute, where an account of it is 



