29 



Subclass PROSOBRANCHIATA. 

 Order CYCLOBRANCHIATA. 



911. Dentalium subquadratum, J/c./, ,\- ILijiden. 



Order SCUTIBRANCHIATA. 

 Neritidae. 



912. Neritella nebrascensis, Meek jf- Hayden. 



Order PECTINIBRANCHIATA. 

 Valvatidae. 



913. Valvata scabrida, Meeh ^- Hayden. 



Vivipai'idae. 



914. Lioplacodes veterna, {Meek <j- Hayden) Meeh. 



Id. 



Id. 



Id. 



Id. 



Class CEPHALOPODA. 



Order TETRABRANCHIATA. 

 Aiiinioiiitidse. 



915. Ammonites biplex, Soiverhy? 



916. Ammonites cordiformis, Meek cj- Hayden. 



917. Ammonites Henryi, Meek .j- Hayden. 



918. Ammonites Wosnessenskii, Grewingk. 



Order DIBRANCHIATA. 

 Beleinuitidae. 



919. Belemnites densus, Mctk S^- Hayden. 



920. Belemnites. 



Russ. Am. 



Id. 



Id. 

 Russ. Am. 



Dak. ; Id. 



Russ. Am. 



SuBEiNGDOM ARTICTJLATA. 



Class A]\]Vi;i.ATA. 



Order TUBICOLA. 



Serpulidae. 



921. Serpula (ined.). 



Id.; Dak. 



