OF CONCHOLOQY. 329 



H. cJiersina, Say. Middle States, Northern States general- 

 ly, (Auot.) Massachusetts; Illinois; Marquette, Mich- 

 igan; Stuart r s Island, Norton Sound; Petropavlovsk, 

 Kamschatka, (Dall.) Lake Tahoe, Cal,, (J. G. Cooper.) 

 Eed Eiver district, (R. Kennicott.) Mantchooria, (Mid- 

 dendorf.) 



H. Whitneyi, Newc. Lake Tahoe, Cal., (Prof. Brewer.) 

 H. Breweri, Newc. Lake Tahoe, Cal. ; Northern Cal., (Prof. 

 Brewer.) 



H. Duranti, Newc, Santa Barbara Island, Cal., (State Geol. 

 Survey.) 



JT. Cronkhitei, Newc. [ ? striatella, (west of Rocky Moun- 

 tains,) Bid., non Anth.] Klamath Valley, Oregon, 

 (Gabb and Cronkhite.) Haywards, Alameda Co., Cal., 

 (var.,) (Rowell.) 



H, conspecta, Bland, Near San Francisco, (J. G. Cooper.) 



M. electrina, Gould. Petropavlovsk, Kamschatka, (Dall.) 

 Red River, (Kennioott.) Illinois ; Marquette, Michigan ; 

 Massachusetts, (Dall.) 



JT. chersinella, Dall. " Big Trees," Calaveras Co., California. 



I am indebted to Dr. Wesley Newcomb for the privilege of 

 describing this shell, which agrees with ao ather m his large 

 and well-named collection. 



