BUB-C LA88 I! 



1 1 1:.\ ACORALLA POEITIDAE 



95 



Family 4. Poritidae. Duna. 



Composite corolla composed of 2)orous sclerenchyma. Corallites small ; septa as a 

 ride only moderately numerous, sometimes represented by rows of trabeculae or lamellae. 

 Theca absent. 



Sub-Family A. SPONGiOMORPHiNAt:. Freeh. 



CoraKum composed of thick trabeculae and strengthened by horizontal synapticulae. 

 Calices very imperfectly differentiated from coenenchyma, and without distinct septa. 

 Dissepiments usually *jntrsely developed. 



Of the genera belonging to this sub-family, Spongiomorpha, Heptastylis, and 

 Stromatomorpha, Freeh, are found in the Alpine Trias (Rhaetic and Zlambach 

 Schichten). These are all tuberous, composite coralla of extremely irregular 

 form. In Spongiomorpha and Heptastylis, six septa are indicated by somewhat 

 regularly disposed columns of trabeculae ; and in the latter form these' are 

 bound together by synapticulae which are projected at equal altitudes, and 

 form perforated horizontal storeys. In Stromatomorpha no radial arrangement 

 of the trabecular septa exists. 



Palaeacis, E. and H. (Sphenopoterium, Meek and Worth), occurring in the 

 Carboniferous limestone of North America and Scotland, possibly also belongs 

 here. 



Sub-Family B. TURBINARINAE. Milne-Edwards and Haime. 

 Septa well developed, compact. Corallites embedded in canaliculated coenenchyma. 



Actinacis, d'Orb. (Fig. 169). Massive or branching coralla. Coenenchyma 

 abundant, granulated ; septa stout, of nearly uniform proportions, columella 

 papillous ; pali in front of all the septa. Cretaceous and Tertiary. 



FIG. 169. 



FIG. 170. 



Actinacis eleyu //>, Hciiss. Upper Cretaceous ; Gosau 

 Valley, Balzkammetgat. , Upper surface, natural Lithuraeu Websteri, Bowerb. sp. Eocene ; Brackles- 



size ; b, Transverse section, enlarged ; c, Longitudinal ham Bay, England, a, Coralluiu, natural size ; b, Four 



section, enlarged (after Reuss). calices enlarged. 



Astraeopora, Blv. Massive coralla. Coenenchyma porous and on upper 

 surface echinulate. Septa of dissimilar proportions ; columella and pali absent. 

 Tertiary and Recent. 



Dendracis, E. and H. ; Cryptaxis, Reuss. Tertiary. 



Turbinaria, Oken (Gemmipora, Blv.) Corallum foliaceous. Coenenchyma 

 tolerably compact and finely echinulate. Septa of similar proportions ; 

 columella spongy. Cretaceous to Recent. 



