47 



108 Turbonilla torquata Gld 



1237 Turbonilla (Mormula) tridentata Cpr. 



2713 Turbonilla Gabbiana 



2079 Turbonilla (Pyrgolampros) Alaskana 



2570 Turbonilla (Pyrgiscus) castanella 



2470 Turbonilla Lovvei D. & B. 



2471 Turbonilla Simpsoni D. & B. 



2472 Turbonilla hypolispa D. &. B. 



2473 Variety stylina Cpr. 



2474 Turbonilla auricoma D. & B. 



2475 Turbonilla aresta D. & B. 



2476 Turbonilla tridentata catalinensis D. & B. 



2477 Turbonilla latifunda D. & B. 

 2346 Turbonilla buttoni Dall & Bartsch. 



562 Turcicula bairdii Dall. Off S. Clemente Isl., in 414 fms. 



1458 Turris (Antiplanes) diaulax Dall. 



1459 Turris (Surcula) ophioderma Dall. 



1460 Turris (Surcula) rhines Dall. 



1461 Turris (Surcula) halcyonis Dall. 

 439 Turritella cooperi Carpenter. 



1114 Turritella jewetti Carpenter. 



1354 Turtonia minuta Fabricius. 



1355 Turtonia occidentalis Dall. 



1115 Tylodina fungina Gabb. 

 1425 Typhis Martyria Dall. 



56 Unio complanatus 



57 Unio Heterodon 



1668 Unio Oregonensis Lea. 



1633 Urosalpinx cinereus 



1605 Uvanilla regina 



2306 Uvanilla unguis Mawe. 



1938 Vaginulus olivacea 



2897 Genus Vallonia Risso, 1826. 



1672 Vallonia minuta Say. 



1673 Vallonia excentrica Sterki. 



1674 Vallonia albula Sterki. 

 1581 Vallonia costata Muller. 



1786 Vallonia costata montana: Rocky Mts. 



2261 Vallonia costata montana Sterki. 



1116 Vallonia cyclophorella Ancey. 



1656 Vallonia gracilicosta Reinh. 



1675 Vallonia parvula Sterki. 



1657 Vallonia perspectiva Sterki. 



1117 Vallonia pulchella Muller. 



2691 Valvata Calli 



2692 Valvata Whitei 



2693 Valvata Utahensis Call. 



2581 Valvata humeralis Say. (See 2679.) 



2679 Valvata humeralis californica 



1118 Valvata sincera Say. 

 45 Valvata tricarinata 



1119 Valvata virens Tryon. 

 3054 Varieties 



2274 Vasum cestrum Brod. 



1120 Velutina cryptospira Middendorf. 



1121 Velutina laevigata Pennant. 



1122 Velutina prolongata Carpenter. 

 2946 Venericardia Alaskana Dall. 



380 Venericardia borealis ventricosa Gould 



