25 



299 Macoma inquinata Desh 

 1176 Macoma lata Gnielin. 

 367 Macoma nasuta Conrad 



889 Macoma obtusa Carpenter. 



890 Macoma sabulosa Spengler. 

 366 Macoma yoldiformis Carpenter 



2145 Macrocallista squalida Sowerby. 1835. 



2146 Macrocallista aurantiaca Sby. 1831. 



2147 Macrocallista pannosa Sby. 1835. 



2148 Macrocallista puella Cpr. 1864. 

 14 Macrocyclis concava 



2231 Macrochasma crenulata 



2450 Macromphalina Californica 

 591 Macromphalina occidentalis 

 64 Macron aethiops 



157 Macron lividus A Ad 



891 Mactra californica Conrad. 

 289 Mactra talcata, Gld 



288 Mactra planulata Conr 



1625 Mactra catiUil'ormis Dall. 



1626 Mactra Hemphillii Dall. 



1627 Mactra dolabriformis Conrad, 1867. 



1628 Mactra polynyma Alaskana 



1635 Mactra (Mactroderma) velota Phil. 1848. 



1636 Mactra (Mactrotoma) nasuta Gld. 1851. 



1637 Mactra (Mactrella) exoleta Gray, 1837. 



1638 Mactra (Mactrella) elegans Sby. 1825. 

 2526 Magilia perattenuata 



178 Mangilia angulata Cpr 



892 Mangilia bicarinata Couthouy. 



893 Mangilia crebricostata Carpenter. 



2451 Mangilia densistriosa Cpr. 



2452 Mangilia Fanchera? 



894 Mangilia funebrale Dall. 



895 Mangilia hemphilli Stearns. 

 485 Mangillia interlirata Stearns. 



896 Mangilia hexagona Gabb. 



897 Mangilia intertossa Carpenter. 



898 Mangilia levidensis Carpenter. 



899 Mangilia merita Gould. 

 2732 Mangilia Painei 



900 Mangilia sculpturata Dall. 



901 Mangilia striosa C. B. Adams. 



397 Mangilia variegata Carpenter. 



398 Variety Nitens Carpenter. 

 2137 Marcia Kennerleyi Rve. 1864. 

 2174 Marcia (Venerella) subdiaphana 

 394 Margarita acuticostata Carpenter 



902 Margarita canfieldi Dall. 



903 Margarita helicina 0. Pabricius. 



904 Margarita lirulata Carpenter. 



2752 Margarita lirulata subelevata Cpr. 



905 Margarita papilla Gould. 



2753 Margarita pupilla salmonea Cpr. 

 2915 Margarita sharpii 



1255 Margarita vahlii Moller. 



3072 Margarites simblus 



907 Marginella Pyriformis Carpenter. 



906 Margarita varicosa Mighels. 

 58 Margaritana undulata 



