On a tieic Genus of Carboniferous Polyzoa. 385 



which are fine encircling stria?. The calice is extremely deep, 

 occupying about one third of the total length of the corallura, 

 cylindroid, and only slightly expanded towards its margin. 

 Eighteen equally developed septa appear in transverse sec- 

 tions of the coral immediately below the bottom of the cup ; 

 and these meet in the centre of the visceral chamber, appa- 

 rently without the intervention of any columella, though 

 seemingly somewhat elevated centrally. There are no traces 

 of either tabulae or dissepiments, and the interseptal loculi 

 appear to extend uninterruptedly from the base to the calice. 

 Towards the margins of tlie calice the septa appear to become 

 obsolete ; but their free edges are unknown. 



Locality and Formation. — Niagara Group (Upper Silurian), 

 Indiana, U.S.A. Collected by Mr. U. P. James. 



XLVI. — On a neio Genus of Carhoniferous Polyzoa. By 

 Professor John Young, M.D., and Mr. John Young, 

 Hunterian Museum, University of Glasgow. 



[Plate X^T B. figs. 1-6.] 



After a careful examination of the literature of Ceriopora 

 gracilis J Phillips, sp., the only conclusion we can come to is 

 that a polyzoon and a coral have been confused. With the 

 coral we have not at present to do ; but to make clear our 

 position, we 'shall quote the generic and specific descriptions. 



"Ceriopora (pars), Goldfuss, 1826; Blainville, 1834; 

 D'Orbigny, 1847. 



" Colony fixed by the base, from which cylindrical dichoto- 

 mouB branches proceed, giving a dendroid aspect. Each 

 branch is provided with several superposed layers, enveloping 

 each otlier, the cells being simply round pores on the surface. 



" Goldfuss, in 1826, placed under Ceriopora a multitude of 

 diverse Bryozoa. In 1834 Blainville considerably restricted 

 the characters of the genus, and only placed in it species pro- 

 vided with several layers of superposed cells, whether the 

 colony is branching or bulbous. Xow, in accordance with the 

 plan we have adopted with all the Bryozoa, we think the 

 name Ceriopora ought to be reserved more specially for the 

 branching dendroid species, the globular non-dendroid species 

 forming the genx^ Beptomulticava. Hence it will be necessary 

 to change the names of several of the Cerioporce admitted in 

 1847 into our ' Prodrome de Paleontologie Stratigraphique ;' 



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