194 



COELENTERATA. 



FIG. 156. Vertical section 

 through the cup of Cyathina 

 cyathus E. and H. = Caryo- 

 phyllia cyathus Lamk. (after 

 M. Edwards). S septa; P 

 pali ; C columella. 



Fam. 1. Turbinolidae. 



projections of the septa. The costae are vertical ridges along the outside of the 

 theca : they are extra-thecal projections of the septa. 



The septa may be confined to the intramesenterial 

 spaces, or they may occur in the intermesenterial 

 as well. They are generally present in cycles of 

 different sizes like the mesenteries, but the number 

 is not always a multiple of six. 



The epitheca when present is outside the theca : 

 it is attached to the edge of the basal plate (Fig. 

 154). 



Section 1. Aporosa. 



Solitary or colonial forms. Hard parts usually 

 solid and imperforate. Theca or wall solid, may 

 be epithecate. Septa solid near the wall, and 

 usually, but not invariably, solid at the further 

 part. Interseptal loculi (i.e., the chambers between 

 the septa) open throughout, or closed more or less 

 by endotheca in the form of dissepiments and 

 tabulae. 



One or more rows of tentacles in relation to the 

 septa and interseptal loculi. The disc with one or 

 more mouths ; a mesentery usually in each inter- 

 septal loculus. Mesenteries usually in multiples 

 of six. 



Corallum simple (solitary), or in colonies. Gemma- 

 tion from the wall or from an expansion of the basal structures. Wall solid. 

 Septal loculi open to the base. Endotheca rarely present. 



(a) Corallum simple, rarely producing deciduous buds. Smilotrochus Ed. and 

 H. ; Onchotroehus Duncan ; Desinophyllum Ehrb. ; Schizocyathus Pourtales ; 

 Fldbellum Lesson ; Rhizotrochus Ed. and H. ; Thysanus Dune. ; Placotrochus 

 Ed. and H. ; Sphenotrochus Ed. and H. ; Nototrochus Dune. ; Placocyathus Ed. 

 and H. ; Platytrochus Ed. and H. ; Turbinolia Ed. and H. ; Stylocyathus d'Orb. ; 

 Conocyathus d'Orb. ; Bistylia T. Woods ; Trematoirochus T. Woods ; Trocho- 

 cyathus Ed. and H. ; Dcltocyathus Ed. and H. ; Odontocyathus Moseley ; 

 Caryophyllia Lmk. (Fig. 156) ; Ceratotrochus Ed. and H. ; Discocyathus Ed. 

 and H.; Brachytrochus Duncan ; Sabinotrochus Dune.; Stephanotrochus Moseley; 

 Anthemiphyllia Pourt. : Fungiacyathus Sars ; Guynia Dune. ; Duncania Pourt. ; 

 Haplophyllia Pourt. 



(b) Colonial ; buds free above their origin ; no exotheca uniting the corallites. 

 Coenocyathus Ed. and H. ; Gemmulatroclms Dune. 



(c) Colony growing from basal expansions; exotheca absent. Pohjcyathus 

 Dune. 



Fam. 2. Oculinidae. Colonial, in the form of branches, espaliers, irregular 

 ramifications on a thick stem ; or massive, or incrusting. Interseptal loculi 

 usually open to the base, but dissepiments or tabulae sometimes occur. Walls 

 of corallites often increasing in thickness exogenously with age, and becoming 

 a solid mass by union with others. Solid intercalicular coenenchyma usually 

 present. Polyps when expanded rising above the wall, or long and exsert, the 

 mouth protruding ; the tentacles 10 to 48 or more, elongated, tips usually 

 swollen or capitate. 



(a) Massive or incrusting colonies. Columella and pali absent, or a false 



