CALIFORNIA STALK-EYED CRUSTACEA. 129 



Carapace strongly convex, wider than long, the whole surface — the 

 large tubercles as well as the intervening spaces — roughened by small 

 short, setose tubercles which vary greatly in size from low, nearl}^ smooth 

 swellings to rough, subcorneal projections. Median region very promi- 

 nent, having a subconical apex a little in front of the middle and a cluster 

 of small, rounded, or subacute tubercles near the posterior end; a large, 

 subconical elevation on the cardiac region in front of which, on either 

 side, is a depressed, comparatively smooth area; median and cardiac areas 

 separated by a comparativelj^ smooth sulcus; a large subconical elevation 

 on the branchial regions and two smaller tubercles on the posterior mar- 

 gin of the carapace. A peculiar smooth wart-like prominence on either 

 side of the median area. Rostrum short and consisting of a strong sub- 

 conical spine above the base of which is a knob bearing two lateral spines 

 or tubercles with (generally) a spine or tubercle above and below the notch 

 between them. A deep, rounded sinus on either side of the front which 

 serves as an orbit, external to which is an acute spine; beyond this spine 

 is a large spine which extends nearly as far forwards as the rostrum and 

 in the sinus between the latter spine and the postorbital there is generally 

 a small spine or tooth. The antero-lateral margin is armed with a variable 

 number (about eight) of prominent spines and several smaller ones; the 

 middle portion is convex, flattened, and produced. A large, knob-like 

 prominence at the postero-lateral angles which is separated from the last 

 antero-lateral spine by a conspicuous sinus. Ocular peduncles two- jointed, 

 thickly set with spines above, and not nearly reaching the tip of the ros- 

 trum. Acicle of the antennae narrow, tapering, much exceeding the tip of 

 the peduncle, and furnished with about thirty strong, smooth, sharp 

 spines. Ischium of the maxillipeds armed within with dark-colored teeth; 

 a tooth on the outer surface near the antero-internal angle; exognath 

 somewhat exceeding the merus. Chelipeds short, the first and second 

 joints with irregular tuberculous projections on the under side; one or 

 more prominent spines on the antero-internal angle of the merus; the 

 lobe on the inner side of the carpus is very large and acute and margined 

 with sharp, spine-like tubercles; spines on the outer surface of the hands 

 large and numerous; four or five large spines on the upper margin of the 

 larger hand and three or four on that of the smaller. Ambulatory legs 

 subequal, strongly tuberculated, quadrangular at the base; carpi and pro- 

 podi subcylindrical but very irregular; dactyls short and stout. The basal 

 abdominal segment is strongly concave behind, especially in the female, 

 and nearly at right angles to the carapace; there are two prominent tuber- 

 cles near the middle and several on the margins; the remaining segments 

 are studded with numerous subconical tubercles; between the median 

 plates there are small, transverse, secondary plates which may be divided 

 by longitudinal fissures; penultimate segment oblong and distally concave. 

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