WEST AMERICAN SHELLS 
Y. montereyensis, Dall, Nautilus VII, p. 29. 
BC Bully yo: 
Y. seminuda, Dall, B. C. Bull. 2, p. 8. 
Y. scssurata, Wall; B.C. Bull. 2, p. 8.) Ar= 
nold, p. 99. 
Vo lanceolata, J: Sbys BoC, Bulls p02: 
Y. lumatula, Say, B. C. Bull. 2, p. 8. 
Y. thracieformis, Storer, B. C. Bull. 2, p. 8. 
Y. arctica, Gray, B. ©. Bull, 2, p.s: 
Y. martyria, Dall, B. C. Bull. 2, p. 9. 
Genus, maltetia, Desmoulins 
M. faba, Dall, B. C. Bull, 2, p. 10; 
M. gibbsi, Dall, B. C. Bulle2, paid: 
M. pacifica, Dall, B. C. Bull..2, p. 11. 
M. kennerleyt, Dall, B. C. Bull. 2, p. 11. 
Sub-order, arcacea 
Family, ARcIDAE 
Genus, area, Lamarck 
A, reticulata, Gmel., San Pedro, southward. 
A. mutabilis, Sby., U.S. N. M. XV, p. 192. 
A. multicostata, Sby., U.S. N. M. XV, p. 192. 
Genus, Barbatia, Gray 
B. gradata, Sby., Nautilus VU, p. 133. 
Genus, vPectuncuius, Lamarck 
P. arcodentiens, Dall, U. S. N. M. XVII, p. 
705. 
Genus, Glycymeris, Da Costa 
G. barbarensis, Conr., Arnold, p. 100. 
G. intermedia, Brod., described in this book. 
G. septentrionalis, Midd., Arnold, p. 100. 
Far north. 
