110 PROCEEDINGS OF THE ACADEMY OF 



doned. On critical comparison between actual specimens, it has appeared 

 that the differences some of which have always been admitted are of too 

 important a character to permit the identification formerly assumed. On the 

 other hand, the following paper discloses an extended network of identifica- 

 tions amongst the fossils from States west of Pennsylvania. But perhaps the 

 most interesting feature of all is the identification of four western species with 

 fossils, contained in the supposed carboniferous conglomerate of western New 

 York. These are Euomplialu.s depressus, Hall, ( = Straparollus Ammon, White), 

 Cypricardia contracta, Hall, (= Edmondia ? bicarinata, Winchell), Edmondia 

 oeqmmarginalis, Win., and A'lorixma Hannibal.ensi*, Shumard.* Considering 

 the small number of fossils as yet discovered in this conglomerate, in New 

 York and these only at one locality (four miJes north of Panama, Chautau- 

 aue County) so considerable a number of identifications is calculated to ex- 

 cite some surprise, and not a little hope, that we are getting glimpses of the 

 clue to a solution of geological difficulties of long standing. 



But further than this, two of the above species Edmondia cequimarginalis 

 and Allorisma Hannibalensin occur in what has been regarded as another con- 

 glomerate, whose position is beneath the first and at the top of the Chemung 

 rocks of Western New York. 



In the light of these identifications, and in the absence of all identifications 

 between western species and those of the Chemung, as well as between the 

 species of this conglomerate and those of the Chemung, it might not seem un- 

 reasonable to doubt its affinities with recognized Chemung rocks, and to sus- 

 pect its continuity with the supposed "carboniferous conglomerate," until 

 observation shall have demonstrated that its stratigraphical position is really 

 below that formation. And further, since we must probably abandon the at- 

 tempt to coordinate the Chemung of New York with the fossiliferous portions 

 of the sandstones and shales of the west lying between the ''Black Slate " 

 and the coal conglomerate, it stems not unlikely that we may yet be able to 

 prove the conglomerates of Western New York to be the attenuated and lit- 

 toral eastern prolongation of those western sandstones and shales at least 

 of the superior and fossiliferous portions of them ; so that the latter would 

 ^tand as a hitherto unrecognized group of strata lying at the very base of the 

 carboniferous system ; while the Chemung rocks of New York fall within the 

 Devonian system, toward which the writer is now inclined to think that their 

 paleontological affinities attract them. 



It yet remains to determine by observations in the field, whether the so- 

 ,;alled "carboniferous conglomerate" of Western New York is really the equi- 

 valent of the coal conglomerate of Ohio ; and whether any actual junction of 

 superposition can be discovered in Western Pennsylvania or Eastern Ohio, be- 

 tween the Chemung rocks in their westward prolongation and the fine grained 

 sandstones and gritstones of the Western States. 



The total number of species at present described from the rocks under con- 

 sideration is about 379, of which 170 were first described by the writer, and 

 four have been recognized as belonging to undescribed genera". The number 

 of .-pecies neticed in the. present paper is 94, of which 3b' are described as new 

 species, and two are made the types of new genera. 



Descriptions and Notes of Species. 

 COXOPOTERIUM n. gen. 



Etymology. K^v&c, a cone, and ttoth^iov, a little cup. 



Generic Characters. Corallum compound, generally free, sometimes adhe- 

 rent, but without a distinct base of attachment. Cells somewhat crowded, 



* The writer is under special obligations to Prof. Hall for the unreserved liberality with 

 which he has been allowed to examine the specimens in his cabinet, as well as for many kind- 

 nesses incident to the generous hospitality of his house. 



[July, 



