42 



1690 Sphaerium nobile Gould. 



2132 Sphaerium solidulum Prime. 



2688 Sphaerium Pilsbryanum 



1075 Sphaerium occidentale Prime. 

 1688 Sphaerium primeanum Classen. 

 1167 Sphaerium raymondi J. G. Cooper. 

 1166 Sphaerium rhomboideum Say. 



52 Sphaerium securis 

 54 Sphaerium similis 



1076 Sphaerium spokani Baird. 



1077 Sphaerium striatinum Lamarck. 



53 Sphaerium sulcatum 



1078 Sphaerium sulcatum Lamarck. 



1079 Sphaerium tumidum Baird. 



3102 Genus Sphyradium Charpentier. 



3103 S: Hasta. Pleistocene, Kansas. 



3104 S: alticolum. Utah, Colo., and Wyoming. 

 Synonymy: — Pupa and Pupilla alticola Ingersoll. 



3105 S: Edentulum. Europe, Asia, etc. 

 1706 Sphyradium edentulum 



437 Spiroglyphus lituella Morch. 



1179 Spisula falcata Gould. 



1639 Spisula (Hemimactra) catilliformis Conr. 1867. 



1640 Spisula (Hemimactra) Hemphilli Dall. 1894. 



1641 Spisula (Hemimactra) planulata Conr. 1837. 



1642 Spisula (Hemimactra) polymyma Stm. 1860. 



1643 Variety alaskana Dall. 1894. 



1180 Spisula planulata Conrad. 



1334 Sportella californica Dall, 1889. Monterey, Cal. 



1335 Sportella stearnsii Dall, 1899. Gulf of Cal. 

 370 Standella falcata Gould 



1569 Standella californica Conrad. 

 472 Standella planulata Conrad. 



1080 Steuotrema germana Gould. 



516 Strombella middendorfii Dall. 



517 Strombella fragilis Dall. 



518 Strombella melonis Dall. 

 2290 Strombus gracilior 

 1439 Subemarginula yatesii 



1081 Succinea hawkinsii Baird. 



1082 Succinea Nuttalliana Lea. 



1924 Succinea Haydeni W. G. Binn. 



1925 Succinea Grosvenorii Lea. 



1926 Forma elongata: Kremmling, Colo. 



1927 Forma rufescens Ckll. Lee Co., Texas. 



1928 Succinea avara Say. 



1929-1933 Forms alba Ckll. (Custer Co., Colo.); wardiana Lea; 

 vermeta Say; compacta Ckll.; major Binn. have been de- 

 scribed. 



1934 Succinea oregonensis Gabbi. 



1935 Succinea chysis Westerl. 



1936 Variety aurelia Martens. 



1937 Succinea annexa Westerl. 



1084 Succinea lineata W. G. Binney. 

 32 Succinea obliqua 



1083 Succinea oregonensis Lea. 

 2262 Succinea retusa Lea. 

 448 Succinea rusticana Gould. 



1085 Succinea sillimani Bland. 

 1886 Succinea stretchiana Bland. 



