9 Septa consist of one or two fan systems of trabeculae. 



Septal teeth never very large and coarse 10 



Septa of more than two fan systems of trabeculae. Septal 

 dentations large and coarse. (Family Mussidael) 25 



10 Septal trabeculae simple or compound. Margins strongly 



dentate 1 1 



Septal trabeculae simple, in one fan system. Margins 

 minutely dentate 21 



11 Septal dentations regular. (Family Fa viidae) 12 



Septal dentations irregular. Reptoid budding. (Family 



Astrangiidae) 1 8 



12 Intratentacular budding. No directive mesenteries except 



in young polyps. (Subfamily Faviinae) 13 



Extratentacular budding. Directive mesenteries in all 

 polyps (Subfamily Montastreinae) 16 



13 Colonies polcoid, corallites united nearly to tops by peri- 



theca. Costate 7avia 



Colonies meandroid, series sinuous, usually long 14 



14 Septa lack internal lobes. Trabecular linkages between 



Centers Viploria 



The larger septa with internal lobes, which are small and 

 narrow. Linkages trabecular or lamellar 15 



15 Trabecular linkage, walls mostly parathecal, valleys 



broad Tdanicina 



Lamellar linkage ColpophyWia 



16 Phaceloid, paliform lobes, papillose columella present. 



Exotheca not vesicular Cladocora 



Plocoid, parietal spongy columella, vesicular exotheca .— 17 



17 Peritheca costate, exotheca vesicular, septal margin regu- 



larly dentate T^tontastrea 



Peritheca almost without costae, very vesicular, appear- 

 ing blistered , Sotenastrea 



18 Colonies reptoid. Septa of first two or three cycles ob- 



scurely dentate and exert (19) 



Colonies plocoid, united basally by peritheca 20 



(19) Corallites united by thin stolon-like expansions. Colum- 

 ella papillary (Oulangia') 



Corallites united by some peritheca. Columella feeble 



(VhyWangid) 

 20 Columella papillose or spongy. All septal dentate ....Astrangia 

 Columella appears lamellar. Only lower cycles of septa 

 obscurely dentate [Colangia') 



105 



