234 DR. J. E. GRAY ON ZOANTHIN^. [Feb. 14, 



skinned Zoanthi, or Zoanthince, the surface of the polype is smooth, 

 soft, and fleshy. 



Duchassaing and Michellot, in their ' Essay on the Corals of the 

 West Indies,' have established some additional genera. 



The base expanded, laminar. 

 1. Mammillifera, Lesueur. 

 Mammillifera, Duchassaing & Michellot, Me'm. Coral, des An- 

 tilles, 51. 



The base slender, subcylindrical, creeping. 

 2. ZoANTHUS, Cuvier, 179; M.-Edw. Coral. 299. 

 Zoantha, Lamk. 



1. ZoANTHUs sociATUS, ElHs, Zooph. 



2. ZoANTHUS ALDERi, Gosse, Biit. Sea Anem. oO.i, t. 9. f. 8, 

 t. 12. f. 5. 



Hab. Coast of Britain. 



See other species (Duchassaing & Michellot, Mem. Coral, des 

 Antilles, 1860, p. 49; Dana, Zoophytes, 423). 



3. Pai-ythoa. 



The polypes close together, arising from a net-like anastamosing 

 linear base. 



Palythoa bertholeti. 



Solitary, rarely irregularly aggregate. 



4. ISAURUS, Gray, Spic. Zool. 8, 1825. 



Isaure, Savigny. 



Isaurus, Duchassaing & Michellot, Mem. Coral, des Antilles, 

 1860, p. 51, t. 8. f. 10. 



Isaurus tuberculatus. Gray, Spic. Zool. 8, t. 6. f. 3, 1825. 



Hab. . B.M. 



This genus and species was described and figured in 1825 from a 

 specimen in the British Museum. 



5. ? Orinia, Duchassaing & Michellot, Mem. Coral, des Antilles, 54. 



Separate. 



6. Pales. 



Body cylindrical ; isolated, solitary, clustered, or sometimes pro- 

 liferous, but each specimen having a separate base ; outer skin 

 smooth, thin, olive-brown, slightly concentrically wrinkled ; the 

 tentacles numerous. The internal laminae numerous, slender, only 



