2195 Variety loxia Dall. 



660 Astarte undata? Gould. 

 2200 Astarte vernicosa 



2615 Asthenotherus villosior Cpr. 



661 Astraliuni inaequale Martyn. 



662 Astralium (Uvanilla) regina Stearns. 



663 Astralium undosum Wood. 



2617 Astrea inaequalis 



2616 Astrea undosa 



1399 Astyris auiantiaca Dall, Am J Con 7:115 (1871),tl5fl3. 



1228 Astyris carinata Hinds. 



1227 Astyris tuberosa Cpr. 



664 Atlanta peroni Lesueur. 

 2027 Atrina Oldroydi 



261 Atys nonscripta A Ad 



130 Avicula Peruviana 



461 Axinaea intermedia Broderip. 



461 Axinaea septentrionalis Middendorf. 



665 Axinaea subobsoleta Carpenter. 



2619 Axinopsis sericatus Cpr. 



2618 Axinopsis viridis Dall. 



666 Barbatia gradata Sowerby. 



667 Barlia'a haliotiphila Carpenter. 

 214 Barleeia haliotiphila Cpr 



79 Barleeia subtenuis 



2620 Genus Bathytoma 

 2695 Bathytoma Carpenteriana 



2621 Bathytoma Keepi Arnold. 

 2694 Bathytoma Tremperiana 

 1218 Bela crebricostata Carpenter. 



668 Bela exarata Moller. 



669 Bela excurvata Carpenter. 



670 Bela fidicula Gould. 

 2576 Bela Grippi 



671 Bela tabulata Carpenter. 



672 Bela trevelliana Turton. 



673 Bela violacea Mighels. 



674 Berendtia taylori Pfeiffer. 

 539 Beringius aleuticus Dall. 



1394 Beringius crebricostatus Dall. 

 538 Beringius frielei Dall. 



1395 Beringius? kennicottii Dall. 



Genus Bifidaria Sterki. 1891. 



2551 Bifidaria agna 



1821 Bifidaria armifera: eastern U. S. 

 1946 Bifidaria Ashmuni 



2686 Bifidaria bilaniellata 



1825 Bifidaria hebes (See 1593). 



1827 Variety Mexicanorum Ckll. Mesilla, N. M. 



1826 Forma saxicola Ckll. Near Silver Cliff, Colo. 



1822 Bifidaria hordeacea: Ariz. — N. M. 

 1824 Bifidaria hordeacella 



1984 Bif. hordeacella parvidens 



2589 Bifidaria pellucida hordeacella 



2001 Bifidaria pentodon 



1957 Bifidaria perversa 



1959 Forma minor Sterki. Nogales, Arizona. 



1828 Bifidaria Pilsbryana Sterki. 



1823 Bifidaria procera 



2926 Bifidaria procera cristata 



