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21:0714 Genus Oyrtodaria Daudin, 1799. 
Shell oblong, gaping at each end; posterior side shortest; 
ligament lange and prominent; hinge thick, teeth 0; epidermis 
black, extending beyond the margins; anterior muscular scar 
long, pallial impression irregular, slightly sinuated. 
21:0715 Cyrtodaria kurriana Dunker, 1862. 
Arctic Ocean; Norton Sound, Alaska; West Greenland. 
21:0716 Genus Lima Bruguiere, 1792. 
Shell equivalve, compressed, obliquely oval; anterior side 
straight, gaping, posterior rounded, usually close; umbones apart, 
eared; valves white, smooth, punctate-striate, or radiately ribbed 
and imbricated; there is usually a thin, brownish epidermis; 
hinge-area triangular, cartilage-pit central; adductor-impression 
lateral, large, double; pedal scars 2, small. 
21:0717 Lima (Mantellum) dehiscens Conrad, 1837. 329. 
Shell equivalve, compressed, obliquely oval, thin, white; an- 
terior side straight; posterior rounded; umbones eared, posterior 
ears acutely pointed; surface smooth, radiately striate with fine 
grooves; hinge-area long, narrow, triangular; cartilage-pit cen- 
tral, prominent; margin finely crenulated. Length 13 mm, alt. 
18.5, diam. 8. Monterey, Cal., to Acapulco, Mexico. 
21:0718 Lima (Limatula) attenuata Dall, 1916. 
Southern Bering Sea; Aleutian Islands; Shumagin Islands, 
Alaska. 
21:0719 Lima (Limatula) subauriculata Montagu, 1808. 
British Columbia, to San Quentin Bay, Baja Cal.; Atlantic. 
21:0720 Genus Leptothyra Cpr. 
Shell small, turbinated, thick, not umbilicated; aperture 
circular, slightly angulated anteriorly. Type L. carpenteri Pils- 
bry (confused with Turbo sanguineus L.) 
21:0721 Leptothyra carpenteri Pilsbry. 411. 3046. 
Alt. 8. diameter 10 mm; shell subconical, reddish; spire 
only slightly elevated! whorls 3 to 4, slightly convex; whorls 
with 9 to 10 fine spiral ridges; tubercle on lower portion of outer 
lip; suture slightly impressed, distinct. Straits of Fuca to San 
Diego, Cal. Japan. 
21:0722. Leptothyra bacula Cpr. 1863 sub Leptonyx. 230. 
Height 2, diameter 2.5 mm; turreted; dark-or ashy in color; 
sculpture firer then in L. carpenteri. Monterey, Cal., to Todos 
Santos bay, Baja Cal. 
21:0723 Leptothyra paucicostata Dall, 1872. 861. 
“Distinguished from L. carpenteri and L. bacula by the coarse 
spiral ribs and deep suture.’’—Arnold. Santa Cruz to Monterey, 
Cal. 
21:0724 Genus Mitromorpha A. Adams. 
Shell small, elongately fusiform; whorls flattened, with re- 
volving lirae, and sometimes longitudinally plicate; aperture nar- 
