184 PKOCEEDINGS OP THE ACADEMY OP 



On report of the respective Committees, the following papers were 

 ordered to be published : 



Observations on American FOSSILS, with descriptions of two new species. 



BY T. A. CONRAD. 



Prof. Cook, of New Brunswick, N. J., has lately received a few fossils from 

 Ocala, Florida, which prove the limestone of that locality to be of the same age 

 as the Shark River marl of New Jersey. The species consist of Globulus 

 alveatus, Con., Venericardia prima, Con., Dosiniopsis alta, Con. These are all 

 Eocene species of California, Maryland and New Jersey. In this rock no 

 doubt occurs Carcharodon angustidens, Agass., of which I obtained a specimen 

 at Tampa Bay, Florida. 



Among Prof. Cook's fossils are a few species from Jasper Co.. Miss. The 

 rock of this county, in which the fossils occur, is stated by Hilgard to be of the 

 Jackson Group, (Upper Eocene.) The species are Ostrea Tuomeyi, Con., Mor- 

 tonia turgida, Con., Pecten Poulsoni, Morton, P. perplanvs, Morton, Carcharodon 

 angustidens, Agass., Orbitolitcs Mantelli, Morton. The former of these I sup- 

 pose to be the shell which Tuomey found so common in the Basilosaurus lime- 

 stone of Alabama, and which he referred to Pycnodonla vesicularis (Gryphsca 

 mutabilis, Morton.) It is very different, however, and may be distinguished by 

 the following characters : 



Ostrea Tuomeyi. Ovate, sublobate, lower valve deep, umbo narrow, rough 

 and unequal in surface, with rough lines of growth; not distinctly plicate ; 

 upper valve convex above, slightly convex below ; with a rough and unequal 

 surface; concentric lamination very prominent, when weathered. 



It differs from P. vesicularis especially in wanting the inner plications about 

 the upper submargins of the interior, and the umbo is much narrower ; it is 

 also a true Ostrea, whilst the vesicularis is the type of the genus Pycnodonta, 

 Fischer, and characterizes the cretaceous era. 



Echinodermata. 

 MORTONIA, Desor. 



Mortonia turgida. Suboval or subpentagonal, swelling medially, with a 

 convex outline ; thin on the submarginal portion of the disc ; ambulacra ellip- 

 tical. 



Allied to M. Rogersi, but larger, thinner round the central prominence, more 

 elevated medially, the depression about the mouth greater, and the anus 

 smaller. It bears about the same relation to Rogersi as Sismendia alta, Con., 

 bears to S. Lyelli, Con. 



Testacea. 

 LIODERMA, Conrad. 



Volutilithes lioderma. This shell has not the characters of Volutililhes, 

 but is covered entirely by enamel, has very oblique columnellar folds, and an, 

 outer lip somewhat ernarginate on the upper part to its juncture with the body 

 whorl ; base deeply emarginate. 



I have not met with this genus in any American Eocene bed. 



SOLENA, Browne. 



Subgenus Leptosolen, Conrad. 



Solena BiPUCATA (siliquaria) Con. Cretaceous. 



[Oct. 



