ANTHOZOA 99 



face. Septa absent or represented by rows of spines. Tabulae 

 numerous, regular, generally extending quite across the visceral 

 chamber. Basal epitheca present. Bala to Carboniferous Lime- 

 stone. Ex. F. gothlandica, Silurian. 



Favosites is related to Syringopora, but the corallites are in 

 contact, and consequently connecting tubes are absent, though 

 probably represented by the mural pores. The living Madreporarian 

 Alveopora agrees in general structure with Favosites, but its walls 

 are less compact, and its basal epitheca is quite small. Some corals 

 (e.g. Koninckia, Ubaghsia) which resemble Favosites are found in 

 the Upper Cretaceous, and are regarded by some writers as links 

 between Favosites and Alveopora. Alveopora has been recorded 

 from the Upper Cretaceous of Portugal. 



Pachypora. Similar to Favosites, but the walls of the coral- 

 lites are greatly thickened, especially near the surface of the coral, 

 by a secondary deposit of carbonate of lime. Silurian to Carboni- 

 ferous. Ex. P. cervicornis, Devonian. 



Alveolites. Allied to Favosites. Massive, encrusting, or 

 branching. Corallites laterally compressed, with thin walls and 

 large mural pores. Silurian and Devonian. Ex. A. labeckei, 

 Silurian. 



Pleurodictyum. Compound, discoidal, attached by part of 

 the base, upper surface slightly convex. Corallites diverge from the 

 centre of the base ; walls thick, with irregular pores. Septa rudi- 

 mentary. Tabula? not numerous, more or less united. A basal 

 epitheca. Silurian and Devonian. Ex. P. problematicum, Devonian. 



XVXichelinia. Similar to Pleurodictyum, but the tabula? are 

 more numerous and form a vesicular tissue, and root-like processes 

 are usually given off from the epitheca on the base of the coral. 

 Devonian and Carboniferous. Ex. M. favosa, Carboniferous. 



Heliolites (fig. 40). Corallum compound, massive or branch- 

 ing, formed of tubes of two sizes ; the larger circular ones are the 

 corallites, between which are the smaller polygonal tubes forming 

 the ccenenchyma. Tabulae occur in both, and in the corallites there 

 are septa which are usually lamellar and are generally twelve in 



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