SCIENTIFIC RESULTS OF EXPLORATIONS BY THE U. S, FISH COM- 

 MISSIONS STEAMER ALBATROSS. 



[Published by permiasion of Hon. Marshall McDonald, Commiasioner of Fisheries.] 



No. XVII. -DESCRIPTIONS OF NEW WEST AMERICAN LAND, FRESH- 

 WATER, AND MARINE SHELLS, WITH NOTES AND COMMENTS. 



/ 

 BY 



Robert E. C. Stearns, 

 Adjunct Curator of (he Depart jiicnt of Mollusks. 



(With Plates xv-xvii.) 



The forms described below are a part of tlie collections in the Depart- 

 ment of Mollusks, U. S. National Museum, and have been received from 

 various sources as indicated in the desciription in each instance. Those 

 from Dr. C. Hart Merriam were either collected by him personally or by 

 collectors employed by him in connection with the biological explora- 

 tions of the Department of Agriculture, under his supervision. Others 

 were received from the Hon. Marshall McDonald, U. S. Commissioner 

 of Fisheries. The latter are a part of the Albatross collections during 

 the year 18S7-'88 made by Prof. Leslie A. Lee and his assistants; and 

 again the collection made in 1855 by the English naturalist, Thomas 

 Bridges, has its representative, contributed by him to the Stearns collec- 

 tion many years ago. 



The Museum is further indebted, directly or indirectly, to other col- 

 lectors whose names appear in connection with the descriptions. For 

 the purposes of comparison figures of certain species contained in the 

 National collections that have not heretofore been figured, or properly 

 figured, are given, with comments thereon, such as naturally arise in 

 the course of a critical examination of related material or forms, the 

 publication of which may be of some service to students of conchology 

 throughout the country who reside at a distance from libraries and 

 museums. 



Proceedings Natiojial Museum, Vol, XIII— No. 813. 



205 



