374: . C. L. Fenton — The Hackberry Stage of 



Animales 

 Bryozoa 



Lioclema occidens (H. & W.). 



Various undetermined species. 

 Brachiopoda 



Crania famelica H. & W. 



Stropheodonta (Leptostrophia) canace H. & W. 



Douvillina arcuata (H. & W.). 



Gypidula comis (Owen). 



Cranaena calvini (H. & W.) ? 



Centronella cf. navicella (Hall). 



Schizophoria striatula (Schloth.). 



Atrypa reticularis (Linn.). 



Atrypa reticularis (Linn.) var. cf. alta Fenton. 



Atrypa hystrix Schlotheim. 



Spirifer whitneyi Hall. 



Spirif er whitneyi gradatus Fenton ( ? ) 



Spirifer ( ? ) hungerf ordi Hall. 



Athyris minutissima Webster. 

 Pelecypoda 



Glossites sp. undet. 



Grammysia (?) sp. undet. 



Paracyclas validalinea Webster. 

 Gastropoda 



Platyostoma mirum Webster. 



Platyostoma pervatum Webster. 



Platyostoma sp. undet. 



Platyostoma, nov. spec. 



Naticopsis rara Webster. 



Turbo ( ? ) strigillata Webster. 



Turbo ( ? ) incerta Webster. 



Holopea tenuicarinata Webster. 



Cyclonema brevilineata Webster. 



Cyclonema subcrenulata Webster. 

 Foraminifera 



Various undetermined species. 



D. The Age and Relationships of the Hackberry. 



There are two geologic formations in this country 

 whose faunas have been considered as being related to 

 that of the Hackberry ; the Independence Shale of Iowa, 

 and the High Point beds of New York. Dr. Calvin was 

 so impressed with the first of these relationships that he 

 even considered that: "During the time represented by 

 the shales and limestones that lie between the Independ- 

 ence and the Lime Creek shales the peculiar fauna of the 

 lower shale horizon, adapted to life on a muddy sea 



