NATURAL SCIENCES OF PHILADELPHIA. 
11 
March 9th. 
Vice President Lea in the Chair. 
Twenty-eight members present. 
The following papers were presented for publication in the Pro- 
ceedings. Prodromus Descriptionis Animalium Invertebratorum 
qusB in Expeditione ad Oceanum Pacificum Septentrionalem a Eepub- 
lica Federata missa, Cadwalladaro Ringgold et Johanne Rodgers ducibus, 
observavit et descripsit W. Stimpson. Pars IV. Crustacea^ Cancroidea 
et Corystoidea.'^ 
" Notice of Remains of Extinct Vertebrata, from the valley of the 
Niobrara River, collected during an expedition under the command of 
Lieut. G. K. Warren, U. S. Topoo;raphical Engineers, to explore the 
region of the Black Hills, by Dr. F. V. Hayden, Geologist to the Ex- 
pedition, by Joseph Leidy, M. D." 
Which were referred to committees. 
Dr. Leidy, in presenting his paper intended for publication in the Proceed- 
ings, observed that it contained characteristic descriptions of twenty-eight spe- 
cies of extinct vertebrates, among which are six carnivora of the canine and 
feline families, iwo rodents, eight ruminants, eight solipeds, three large pachy- 
derms, and one turtle. In relation to the eight solipeds, he stated they belonged 
to six genera : Equus, Hipparion, Protohippus^ Merycliipj)m^ Hypohiprpus^ and 
Parahippus. The two latter constitute with Anchitherium a distinct group ; the 
three former constitute another group ; and the fourth one is an intermediate 
form. The remains of Uquus, indicating one species, are undistinguishable from 
the corresponding parts of the domestic horse. 
Dr. L. further remarked, since he had had the opportunity of inspecting the 
numerous equine remains from the Niobrara, he was inclined to believe that the 
remains of the horse found in the post-pliocene deposits of the United States, 
indicate two speeies. Of these the remains of one are undistinguishable from 
corresponding parts of the recent horse, and are the representative of the E. pri- 
migenius of Europe, and may be distinguished by the name of E. fraternus. The 
other species relates to the E. pliddens of Europe, and like it is characterized by 
the comparatively complex arrangement of the enamel folding in the upper 
molar teeth. He had formerly named it E. americanus^ but as this name 
had been previously applied to a South American species, he would now propose 
for it that of E. compUcatus. The equine remains referred to, together with those 
of a small species of Hipparion from the post pliocene deposit near Charleston, 
S. ■C., and those of a species of Anchitherium from the miocene deposit of the 
Mauvaises Terres, Nebraska, appear to indicate the former existence of twelve 
species of seven genera of the family of solipeds in this country. From these 
facts it would appear as if the equine family was becoming extinct, as it is now 
represented by the sole genus Equus. 
Dr. Hammond said the sections of jet he presented this evening were from a 
vein eighteen inches in thickness, at Oevolleta. Under the microscope they 
exhibited the woody structure very beautifully. 
Mr. Lesley exhibited fragments of conglomerate, from under the coal, from the 
top of Blossburg Mountain, showing apparently the impression of a Calamite, 
which seemed to have marked or moulded even the pebbles themselves. 
Mr. Lea was inclined to ascribe the marks upon the fragments exhibited, rather 
to the groving or scratching of one rock by another after fracture, as seen in the 
slickensides. 
Mr. Lesley had examined the locality for scratches, but bad found no s^^ch fissure 
as that suggested by Mr. Lea, besides the beds at the spot are nearly horizontal , 
1858.] 
