I.,.„ 



HEXACOKALLA 



103 



corallites arising from periphery by costal gemmation. Common outer wall 

 naked, striated. Cretaceous and Tertiary. 



Leptophyllia Reuss (Fig. 1 60). Corallum simple, conical or cylindro-conicäl, 

 with superficial calice. Septa numerous, thin, regularly-toothed ; solid or only 



Cyathoseris siCbregxdaris Keuss. Oligocene ; Monte Carlotta, near Viceiiza, Italy. 

 a, Top view ; h, Side view, natural size. 



Fig. 160. 



Leptophyllia sinuosa 

 From. Neocomian ; St. 

 Dizier, Haute - Marne. 

 Natural size. 



partially perforate. Thin dissepiments present. Thin epitheca present. 



Thamnasteria Lesauv. {Thamnastraea auct., of which T. lamourouxi is the 

 type.) Jura. Lophoseris E. and H. ; Agarkia Lam. ; Siderastrea Blv., etc. 

 Tertiary and Eecent. 



Family 3. Anabaciidae Duncan. 



(Pseudoasfraeinae and Pseudoagaricinae Pratz ; Microsolenidae Gregory.) 



Simple coralla, or composite, hasally expanded or massive colonies. Septa 

 numerous, perforate, and composed of calcareous hodies (traheculae) arranged in 

 vertical or fan-shaped rows (trabeculate). Theca hetween individual corallites ahsent, 

 hut may he present on under side of corallites or on lower side of the common 

 stock. Interseptal loculi with synapticula and dissepiments. Abundant from Trias 

 to Cretaceous ; rarer in Tertiary and Recent. 



Änahacia d'Orb. Simple, free, discoidal, or lenticular coralla, with flat 

 base. Upper side vaulted, calice slit-like. Septa very numerous, thin, and 

 united by synapticulae. Theca absent. Jurassic ; Europe. 



Genabacia E. and H. Like the preceding but composite, the central calice 

 being surrounded by a row of smaller calices. Jurassic ; Europe. 



Micrabacia E. and H. Cretaceous ; Europe. 



Omphalophyllia Laube. Simple, turbinate or sub-cylindrical, attached, 

 and covered with epitheca. Septa very numerous, upper edges granulated. 

 Calice shallow, columella styliform. Alpine Trias. 



Cyclolites Lam. (Fig. 161). Simple, free, discoidal, upper side vaulted, 

 lower flat and covered with corrugated epitheca. Septa very thin, extending 

 to the centre, extremely numerous, composed of vertical rows of traheculae, 

 and united by synapticulae and dissepiments. Very abundant in Cretaceous, 

 rare in Jurassic and Eocene. 



Dimorpharaea From. (Fig. 162, A, B). Composite, laterally expanded and 

 pedunculate, or mushroom-shaped coralla. Common wall restricted to lower 



