CLASS GASTROPODA 
321 
preserved specimens being rendered much brighter by the closely placed 
fascicles of brilliant vermilion spines. The valves are wholly concealed, 
white or flesh-colored, entirely lacking the outer colored layer (tegumen- 
tum) of other Chitons; their edges are more or less thinned and crenulated 
by radial striae. Anterior valve having the apex at the posterior third, and 
with 4 to 7 slits. Intermediate valves having the apex near the posterior 
third; formed of two large anterior lobes expanded at the sides, and two 
smaller, narrow posterior or near the posterior third; deeply sinused in the 
rear, and usually having a slit on each side of the sinus. Girdle leathery, 
thick red, densely covered with countless minute fascicles of vermilion 
spinelets. Length, 15 to over 20 cm. (Tryon and Pilsbry, Manual of Con- 
chology.) 
Type in Academy, St. Petersburg. Type locality, Kamchatka. 
Range. Bering Island, Kamchatka, Kuril Islands and Okhotsk Sea, 
Aleutian Islands, Cook’s Inlet, to San Miguel and San Nicolas Islands, 
California. 
Genus AMICULA Gray, 1847 
Valves almost covered by the extension of the girdle over them, leaving 
only a small rounded or heart-shaped portion exposed at the apex of each; 
posterior borders of valves produced backward in rounded lobes at each 
side, the lobes completely separated by a posterior sinus having the 
tegmentum at its apex. Posterior valve having a posterior sinus and one 
slit on each side. Girdle more or less pilose, often having pore rows. The 
essential features of Amicula are its small exposed portion or tegmentum, 
situated at the posterior edge, and not extending forward to the sinus, its 
Mopaloid posterior valve, short contour, and short gills. (Tryon and 
Pilsbry, Manual of Conchology.) 
Type. Chiton vestitus Sowerby. 
Range. North Pacific and Atlantic Oceans. Fossil, Pleistocene Drift, 
Lower Canada. 
Amicula amiculata Pallus, 1786 
Nova Acta Academiae Scientiarum Imperialis Pctropolitana, 2:235; PI. 7, figs. 26-30. 
Maximus est omnium huius generis qui hucusque innotuerunt, quippe 
qui saepe in longitudinem sex pollicum angulicorum (Stellero obseruante) 
excrescit, mihique ipsi inter minores plures, quadripollicaris, licet siccus, 
e Curilis insulis adlatus est. (Pallus.) 
Valves covered with cartilage, scabrous and subverrucose outside, the 
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