xlvi BRITISH FOSSIL CORALS. 



confluent, and not circumscribed in the compound species. Septa not distinct from the 

 costse, and formed by complete, imperforate laminae, with the edge dentate, and the sides 

 covered with styliform or echinulate processes, which, in general, meet so as to constitute 

 numerous synapaticula, or transverse props, extending across the loculi like the bars of 

 a grate. No dissepiments or tabulae, so that no part of the visceral chamber is completely 

 closed. Walls basal, in general porous. The compound species increasing by sub- 

 marginal gemmation, and not by fissiparity. 



First Tribe— CYCLOLITINtE. 



Corallum simple. Plate or basal wall having a well-developed epitheca, presenting 

 concentric folds. 



1. Genus Cyclolites. 



Lamarck, Syst. des Anim. sans Vert., p. 369, 1801. 



Corallum circular, or nearly so, and covered with an immense number of very thin 

 septa. Fossula oblong, narrow, and shallow. The small septa in general united to those 

 of the older cycla. 



Typ. sp., Cyclolites elliptica, Lamarck, loc. cit., p. 234. 



2. Genus Pal^eocyclus. 



Milne Edw. and J. Haime, Comptes rend, de l'Acad. des Sc, vol. xxix, p. 7.1, 1849. 



Corallum circular. Fossula deep, very broad, and circular. Septa thick and not 

 numerous ; none of them cemented together. 



Typ. sp., Palceocyclus porpita, Milne Edw. and J. Haime, loc. cit.; Madrepora porpita, Fougt, Lin. 

 Amcen. Acad., t. i, tab. iv, fig. 5. 



Second Tribe— FUNGIN^E. 



Corallum simple or composite. Plate or basal wall without an epitheca, in general 

 strongly echinulate, and porous. 



3. Genus Fungi a. 



(In parte) Lamarck, Syst. des An. sans Vert., p. 369, 1801; Dana, Zooph., p. 287, 1846; Milne Edw. 



and J. Haime, Comptes rend., t. xxix, p. 71, 1849. 



Corallum simple, subdiscoidal. Septa very numerous, and united so as to appear 

 ramified. Basal wall strongly echinulate, and perforated in an irregular manner. 



Typ. sp., Fungia patellaris, Lamarck, loc. cit., p. 236 ; Milne Edw. and J. Haime, Ann. des Sc. Nat., 

 t. ix, pi. vi, fig. 1. 



