CLASS I PICA TION. 



15 



forate compact coenenchyma ; are provided with six, twelve, or 

 twenty-four septa, sometimes obsolete ; and are intersected by 

 complete transverse tabulae. A rudimentary columella is pres- 

 ent. The animal of Pocillopora has been examined by Profes- 

 sor Verrill {loc. jam cit.), who describes the polypes as being 

 " exsert in expansion, with a regular circle of twelve nearly 

 equal, stout, tapering tentacles surrounding the circular disc ; 

 and twelve internal, radiating, fleshy lamellee show through 

 the disc. Thus they closely resemble the polypes of Stylo- 

 pJiora, Porites, and Madrepora, which are among the most 

 typical of the true polypes. The existence of stellate cells 



Fig. 3. — A, Portion of the corallum of Pocillopora aspera, var. lafa, Verrill, of the natural 

 size ; B, Part of the surface of same enlarged ; c. Section of the corallites of the same, 

 showing the columella, enlarged ; D, Vertical section of the same, enlarged, showing 

 tabulce. (After Dana.) Recent. 



with six or even twelve well -developed radiating septa in 

 several species of Pocillopora {e.g., P. eloiigata, Dana, P. 

 plicata, D., P. stellala, V.), should be sufficient evidence that 

 such Corals have no Acalephian affinities whatever, even 

 without the conclusive evidence derived from a study of the 

 living polypes " (Amer. Journ. Sci. and Arts, ser. 3, vol. iii. 

 p. 191). 



It cannot be doubted, then, that Pocillopora, Lam., is a true 

 Aporose Zoantharian, most nearly allied to the OcttlinidcE ; but 

 there is some doubt as to the forms which should be associated 

 with it, since in none of the allied types are we acquainted with 

 the structure of the animal itself The corallum of Seriatopora, 

 Lam., however, so closely resembles that of Pocillopora in its 



