138 
GEOLOGY OF THE THIRD DISTRICT. 
List of Fossils from the Reports , etc. of T. A. Conrad, which are found in the Onondaga 
limestone, and, identified and named by him to this period,. 
Testacea, or Shells. 
Avicula pecteniformis. 
Cypricardites inflata. 
Bellerophon curvilineatus. 
Pleurotomaria poulsoni. 
— unisulcata. 
Crustacea. 
Asaplius aspectans. 
It is possible that D. raricosta may be the same with D. undulatus of the wood-cut; but the latter is 
not rare as to number of ribs, having not only the same with D. macropleura and D. pachyoptera, but 
with an undescribed Delthyris found by Dr. Budd of Lewis county, in the Trenton limestone of that 
county, and having characters somewhat intermediate to macropleura and undulatus. 
Delthyris raricosta. 
Strophomena gibbosa. 
— perplana 
Atrypa nasuta. 
— unisulcata. 
— acutiplicata. 
