74 



PROr. p. MAETIIS" DrNCA^'s REYISION OF THE 



covered with a complete epitheca, forming strong circular ridges, 

 wanting here and there; Calicos round. No columella (?). 

 Septa broad, slightly exsert, uniting at the axis. Eudotheca well 

 developed. Gemmation lateral, and buds pass up parallel with 

 the parent. 



Distribution. — Fossil. Oolite : Europe, England ? 



V. Alliance PAL^ASTR^OIDA. 



Astrseidse which increase by gemmation from the wall of the parent, 

 and also from the calice. Septal number irregular. Costae occasionally 

 remarkably developed. 



Genus Heterophyllia, M'Coy. 

 Genus Battersbyia, Ed. & H. 



Genus Heterophyllia, M^Coy, amended in Fhil. Trans. Boyal 

 Soc. 1867, p. 648. 

 Colony of long and slender corallites, free. Gemmation 

 around the calicular margin. Septa either irregular in number 

 and arrangement, or are only six in number and regularly 

 placed. Costse well developed, may be tubercular, spined, and 

 flexuous. "Wall thick. Eudotheca dissepimental. Epitheca 

 absent. Columella absent or produced by junction of the 

 septa. 



Distribution. — Fossil. Carboniferous limestone : United King- 

 dom. 



Genus Battersbtia, Fd. ^ H., amended in FJiil. Trans. Boyal 

 Soc. 1867, p. 648. 



Colony fasciculate. Corallites tall, distant, or close and 

 crowded, free, except when arising from a parent, very variable 

 in dimensions in the same colony, or else subequal. Calices and 

 corallites, on section, circular in outline. Columella abseut or 

 produced by union of septa. Septa very unequal in size and 

 number, from 6, 12, to 52 in number. Eudotheca vesicular and 

 abundant. Gemmation from the walls of corallites, and the 

 buds have five septa or more ; also by budding from the inter- 

 septal spaces of those buds, of gemmules which develop six septa. 

 There is no epitheca. Corallites without coenenchyma around 

 them, but often surrounded by Stromatoj>ora. 



Distribution. — Fossil. Devonian : England. 



