PLATE VI. 



Afagasella radiata Dall ; 6/1 [N. W. America]. 



Thecidium Barretti Davidson ex Woodward; 5.1. Page 205. 



Modiola polita Verrill & Smith ; 42.5. Page 234. 



Terebratula Bartlettii Dall ; 40.0. Page 200. 



Pecten (Janira) hemicyclica Ravenel ; 4.0 ; inside upper valve of 



young shell. Page 207. 

 Terebratula incerla Davidson ; 11.6 ; interior. Page 201. 

 Same, horizontal view of loop. 

 Modiolaria lateralis Say ; 7.6. Page 236. 

 Area ectocomata Dall ; 46.0. Page 243. 

 Tellina sybaritica Dall ; 7.0. Page 277. 

 Crassatella floridanaDaW; 11.0; young shell. Page 256. 



