21 



1814 Holospira 3Iearnsii Dall. 



2258 Holospira mesolia 



2207 Holospira oaxacana 



1667 Holopira pas or. is 



1819 Holospira pilsbryi Dall. 



2209 Holospira regis 



1817 Holospira Roemeri 



2211 Holospira tantalus 



2508 Hopkinsia 



2509 Hopkinsia rosacea 



6 Hyalina arborea 



1199 Hyalina biimeyanum Morse. 



10 Hyalina exigua 



12 Hyalina fulva 



7 Hyalina indentata 



8 Hyalina lineata 



1198 Hyalina milium Morse. 



9 Hyalina minuscula 



13 Hyalina multidentata 

 1197 Hyalina radiatula Alder. 



11 Hyalina viridula 



839 Hydrobia calii'ornica Tryon. 

 194 Ianthina bifida Totten 



2710 Ianthina communis 



2711 Ianthina exigua Lam. 

 2709 Ianthina globosa Swainson. 

 2560 Ilyanassa obsoleta 



206 Isapis fenestrata Cpr 

 430 Isapis obtusa Carpenter. 



2353 Ischnochiton acrior 



2442 Ischnochiton biarcuatus 



2355 Ischnochiton clathratus 



2356 Ischnochiton conspicuus 

 1548 Ischnochiton cooperi Cpr. 



2354 Ischnochiton didymus Bartsch. 



1275 Ischnochiton interstinctus Gould. 

 2892 Ischnochiton magdalenensis Hinds. 



2758 Ischnochiton magdalensis Hds. 



2759 Ischnochiton Mertensii Midd. 



2890 Ischnochiton mertensii Midd. 



2443 Ischnochiton punctulatissimus Cpr. 



840 Ischnochiton radians Carpenter. 

 2406 Ischnochiton raymondi Pilsbry. 

 2889 Ischnochiton regularis Cpr. 

 2757 Ischnochiton regularis Cpr. 



1276 Ischnochiton reteporosus Carpenter. 

 1445 Ischnochiton sarcosus Dall. 



1702 Ischnochiton scabricostata Cpr. 



1702 Ischnochiton scabricostat Cpr. 



1444 Ischnochiton Stearnsii Dall. 



2891 Ischnochiton sinudentatus Cpr. 



1277 Ischnoradsia mertensii Middendorf. 



1278 Ischnoradsia trifida Carpenter. 

 385 Janira dentata Sowerby 



213 Jeffreysia translucens Cpr 



841 Katherina tunicata Wood. 

 315 Kellia laperousii Desh. 



842 Kellia rotundata Carpenter. 

 459 Kellia suborbicularis Montagu. 



843 Kennerlia bicarinata Carpenter. 



