CLASS GASTROPODA 
283 
divergence, 105°. (Carpenter.) (Tryon and Pilsbry, Manual of Con- 
chology.) 
Type in ? Type locality, Monterey, California. 
Range. Catalina Island to Monterey, California. 
Ischnochiton sinudentatus Carpenter, 1892 
Tryon and Pilsbry, Manual of Conchology, 14:128. 
Shell oval, much elevated, reddish; jugum acute; mucro median, 
scarcely elevated; entire surface minutely granulose. Central areas having 
about 12 subparallel bars, which pectinate the front margin, their inter¬ 
stices decussated; lateral areas having 3-4 granulose radiating lirae, the 
anterior valve with 26, posterior valve 24 such lirae. Interior: anterior 
valve with 10, central 1, posterior valve 9 slits; teeth acute; eaves con¬ 
spicuous, subspongy, crenulated by the sculpture; sinus wide, short, lami¬ 
nate with about 6 teeth. Girdle having moderate-sized, wide, conspicuously 
striated, rather regularly imbricating scales. Length, 15; width, 7 l / 2 mm.; 
divergence, 100°. (Carpenter.) (Tryon and Pilsbry, Manual of Con¬ 
chology. ) 
Type in ? Type locality, Monterey, California. 
Range. Known only from type locality. 
Ischnochiton asthenes Berry, 1919 
Proceedings of the California Academy of Sciences, series 4, 9: No. 1, PI. 8. Lorqui - 
nia, January 1919. 
Shell small, carinate, with convex side slopes. Surface granulose. Head 
valve with 11-12 low, rounded flutings, bearing 2-4 minute pustules each. 
Median valves with lateral areas distinctly raised, bicostate, each rib bear¬ 
ing 2-5 small pustules; central areas with 15-18 narrow, granulose, longi¬ 
tudinal ribs, finely interlatticed between, but becoming obsolete on jugum. 
Slit formula 9, 1-1, 12. Girdle scales small, convex, delicately ribbed. 
Color of shell yellowish-brown, mottled deeper. (Berry.) 
Type in Berry Collection. Type locality, White's Point, Los Angeles 
County, California. 
Range. Known only from type locality. 
Ischnochiton stearnsii Dali, 1902 
Proceedings of the United States National Museum, 24:557. 
Chiton of moderate size, yellowish or buff color; the girdle yellowish- 
white, covered with subcylindric, blunt, smooth, close-set, large spines, the 
ends of which have a pebbly appearance, mixed with a smaller proportion 
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