LONSDALE ON EOCENE CORALS FROM N. AMERICA. 511 



ford the requisite information for determining ; but it is believed 

 that M. Ramond may have associated with his O. nuda, ob- 

 tained in the Pyrenees, the 0. inclusa from Artois, without 

 a full consideration of all the structural characters, or on a 

 mere resemblance in the nature of the canals and the fibral 

 tissue. How far this supposition, and the conjecture that O. nuda 

 does not belong to Ventriculites ; may be correct, an examination 

 of specimens only can decide. In attempting, however, to ascer- 

 tain the nature of certain American fossils, and the most nearly 

 allied known genus, it was found that essential differences existed 

 between those remains and V. alcyonoides as well as V. radiatus ; 

 while so far as M. Ramond's figures of Ocellaria nuda, particu- 

 larly (1 b.), could be relied on, a considerable agreement was appa- 

 rent ; and it has therefore been deemed advisable to consider the 

 Mont-Perdu fossil as distinct from Ventriculites, and to associate 

 generically with it these fossils from America. 



Ocellaria ramosa consisted apparently of a fibrous body not 

 divisible, as in Ventriculites, into layers of different composition, 

 and penetrated by irregularly arranged canals — also of a partially 

 developed, thin, investing, non-fibrous crust. Neither the solid 

 casts representing the inter-fibral lacunae, nor those which occupied 

 the canals exhibited in the fossil any signs of contraction : there was 

 also a total want in the calcareous matrix of all indications of a 

 thick, gelatinous, coriaceous, or other covering. The canals sprung 

 apparently from the axis of the specimens, and after ranging for 

 some distance more or less vertically, diverged outwards in every 

 direction, the plane of the opening coinciding with that of the sur- 

 face. At the lower extremity they blended with the fibral struc- 

 ture ; and it is believed that they were, to a certain extent at 

 least, progressively obliterated. In other portions of their range 

 they were often penetrated irregularly by simple fibres, and some- 

 times in a manner which gave the transverse section a star-like or 

 radiated aspect. Mr. C. B. Rose, of Swaffham, has pointed out a 

 similar appearance in Ventriculites. * In transversely fractured 

 specimens, the calcareous matter, which occupied the canals, pre- 

 sented generally a smooth but irregularly impressed surface, which 

 had been clearly moulded on a soft or yielding material ; and in 

 more than one instance proofs were obtained of two successive 

 similar surfaces at distances exceeding a line, and their position 

 was shown by a cross fissure or narrow interval, due to the re- 

 moval of the original body. In some cases the canals were few in 

 number or distant ; but in one specimen they were so numerous 

 as to occupy nearly the whole of it, the interspaces being limited 

 to a single series of very short fibres or merely connecting pro- 

 cesses, without the least signs of contractions. The partially 

 developed outer crust presented its greatest thickness and persist- 

 ence near the base of the specimen, where it completely concealed 

 the fibres and canals ; but in other places its extent was limited, 



* Loudon's Mag. Nat. Hist. vol. ii. p. 335. fig. 93 b. 1828 — 1829. 



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