393 



Homotrypella rustica Ulrich. 



Rhombotrypa crassimuralis (Ulrich). 



Dinorthis subquadrata (Hall). 



Hebertella occidentalis (Hall). 

 *Platystrophia acutilirata (Conrad). 

 *Platystrophia acutilirata senex Cumings. 

 *Rafinesquina alternata (Emmons). 

 Rbyncbotrema denatatum (Hall). 



Strophoniena vetusta James. 



Strophomena planumbona (Hall). 



Strophomena sulcata (Verneuil). 



Zygospira modesta (Hall). 



In comparing the fauna of this cut with tbe numbers, one and two. of 

 the Richmond type section, we find that many species that appear in the 

 type locality are not found at Spades, but those that do appear at Spades 

 are undoubted Whitewater species. Those that are limited to and charac- 

 teristic of, the Whitewater, are: Homotrypa wortheni (James?) Platy- 

 strophi aacutilirata senex. Cumings. Byssonychia obesa Ulrich, and 

 Lophospira trophidopora (Meek). 



Twenty-four species were identified from Spades, three of which are 

 new and undescribed. The description and discussion of their morpb> 

 logical structure will be given in a subsequent paper. 



