CLASS GASTROPODA 
251 
strong concentric resting stages and fine, low, close-set, rounded pustules; 
posterior plate large, similarly sculptured, with a prominent mucro nearer 
the posterior than the anterior edge of the plate, the anterior and posterior 
areas hardly defined; intermediate valves with the lateral areas more or 
less irregularly concentrically ridged, the pleural and jugal tracts less 
distinctly so, the whole covered with uniform pustulation and the inner 
areas defined very obscurely by faint depressions; though angular, the 
jugum is not beaked anteriorly. Long, of animal, about 35; lat. (with 
dry girdle), 9; alt., 6 mm. (Dali.) 
Type in United States National Museum, No. 109019. Type locality, 
off the Queen Charlotte Islands, B.C., “Albatross” Station 3342, in 1,588 
fathoms. 
Range. Bering Sea, 688 fathoms, Queen Charlotte Islands. 
SECTION XIPHIOZONA Berry, 1919 
Lepidopleurus nexus Carpenter, 1864 
Supplementary Report , British Association for the Advancement of Science, 650. 
Tryon and Pilsbry, Manual of Conchology, 14:11. 
Like asellus: scarcely sculptured: mantle-margin with striated chaffy 
scales, like magdalensis, interspersed with transparent needles, 20-80 fm. 
(Carpenter.) 
Shell small, whitish-ashen, valves gothic-arched; lateral areas scarcely 
defined; entire surface ornamented with series of subquadrate granules, 
the series longitudinal upon the central, radiating upon the lateral areas 
and end valves, very close, scarcely interrupted. Jugum elevated, subacute; 
umbones inconspicuous. Mucro conspicuous, median. Inside with strong 
sutural lobes and a wide plane sinus to the middle valves; insertion plates 
obsolete. Girdle having narrow, close, striated scales, and needle-shaped, 
crystalline bristles here and there and around the margin. (Carpenter.) 
Length, ; breadth 4 /z mm.; div. 90°. (Tryon and Pilsbry, Manual of 
Conchology.) 
Type in United States National Museum. Type locality, Catalina 
Island, California. 
Range. Catalina Island to Gulf of California. 
Described as Leptochiton nexus Carpenter. 
Lepidopleurus heathi Berry, 1919 
Lor quinta, January 1919. 
Shell small, strongly convex. Anterior valve with 100 or more radial 
series of flattened grains. Median valves similarly sculptured, the lateral 
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