CANANDAIGUA AND NAPLES QUADRANGLES 



57 



tated, were so unfavorable that the organisms were able to 

 advance but a little in the line of species development and yet 

 they apparently acquired the power of reproduction and mani- 

 fested themselves in these arrested conditions probably for 

 several generations. These fossils were studied by the writer 

 some years ago, and have been more exhaustively examined of 

 late by Dr F. B. Loomis from material collected all along the 

 line of outcrop of the layer. 



The specimens are to be extracted from the rock only with 

 great labor but it is to be expected that forms present at 

 one place wiH appear at others and hence the entire list of the 

 known species is here appended. It will be observed that the 

 designations used in Dr Loomis's list here given indicate muta- 

 tions only from the types of Hamilton species and not deep seated 

 specific differences. 



Crustaceans 

 Beyrichia dagon Clarke 

 Entomis pro-sepbina Loomis 

 Crypbaeus boothi var. calliteles 



Green 



Cephalopoda 

 Bactrites (sp.) ? mut. parvus Loomis 

 B. (sp.) mut. pygmaeus Loomis 

 Orthoceras nuntiuni Hall 

 O. scintilla (?) mut. inepbisto Clarke 

 O. subulatuin mut. pygmaeura 



Loomis 



Tornoceras uniangulare mut. astarte 



Clarke 

 T. uniangulare Conrad 



Ptcropods 

 Teutaculites bellulus? mut. stebos 

 Clarke 



T. gracilistriatus mut. asmodeus 

 Clarke 



Gastropods 

 Loxonerna delpbicola mat. uioloch 



Clarke 

 Pleurotomaria 



P. itys mut. pygmaea Loomis 



P. capillaria mut. pygmaea Loomis 



Macrocbilina bauiiltouiae mut. pyg- 



uiaea Loomis 

 M. bebe mut. pygmaea Loomis 

 Diapborostonia lineaturn mut. belial 



Clarke 



Lamellibranchs 



Conocardium eboraceum mut. pyg- 



maeuin Loomis 

 Buchiola retrostriata mut. pyginaea 



Loom is 



Grauimysia constricta mut. pygmaea 

 Loomis 



Paracyclas lirata mut. pygmaea 

 Loomis 



Palaeoneilo constricta mut. pygmaea 

 Loomis 



P. plana mut. pygmaea Loomis 

 Leda rostellata mut. pygmaea 

 Loomis 



Nuculites oblongatus mut. pygmaeus 

 Loomis 



N. triqueter mut. pygmaeus Loomis 

 Nucula varicosa mut. pygmaea 

 Loomis 



N. corbuliformis mut. pygmaea 

 Loomis 



X. lirata mut. pygmaea Loomis 



