534 BULLETIN 129, UNITED STATES NATIONAL MUSEUM 



inner side with two rows of short spines or pointed teeth. Hand 

 short and stout; fingers stout, dactylus much the longer. 



Description. — Near astroides; carapace longer, outline more pent- 

 agonal; lateral and posterior margins, instead of thin and acutely 

 dentate, are thick, the posterolateral margin nearly transverse and 

 furnished with seven unequal lobes; antero-lateral angle more 

 strongly marked, margin sub-entire; hepatic region more prominent. 

 Reticulating ridges of surface smooth; instead of prominent, acute 

 tubercles at intervals, there are rounded tubercles covered with 

 depressed granules. Antero-internal angle of basal antennal joint 

 not reaching front. A row of six or seven acute tubercles on en- 

 dognath, the posterior tubercle much the largest. No large spine 

 on sternum at base of cheliped. Protuberances of chelipeds rounded 

 lobes or tubercles, except those of dactylus. Arm shorter and less 

 thigh-shaped than in astroides; the largest tubercles are the one near 

 distal end of outer-upper border, and one near proximal end of inner- 

 lower border. Of the tubercles on the manus, the middle one of 

 the upper row is by far the largest. Fingers shorter than in astroides, 

 gaping in larger cheliped; dactylus armed with three or four small 

 spines or sharp-pointed tubercles on inner surface. Lower border 

 of propodus armed with six triangular, acute teeth. I^egs with 

 surface little rough save on dactylus; marginal prominences either 

 lobes or tubercles except on lower edge of propodus and on dactylus 

 where they are sharp denticles. 



Measurements. — Female, holotype, length of carapace 18.4, width 

 of same 25, length of cheliped 27 mm. Male (21577), length of 

 carapace 17.9, width of same 24.7, length of cheliped 39.3 mm. 



Range. — West coast of Mexico: Southern part of Gulf of California 

 and off Cape St. Lucas. Depth, 8 to 31 fathoms. 



Material examined. — See table, page 535. 



Genus SOLENOLAMBRUS Stimpson 



Solenolambrus Stimpson, Bull. Mus. Comp. Zool., vol. 2, 1871, p. 132; type, 



S. typicus Stimpson. 

 Pisolambrus A. Milne Edwards, Crust. R6g. Mex., 1878, p. 157; type, P. 



nitidus A. Milne Edwards. 



Carapace pentagonal, more or less broader than long; posterior 

 side of pentagon much the shortest, the other four sides about equal. 

 Margin acute on all sides, forming a slight crest. The upper surface 

 is naked, glossy, strongly convex, and bears four protuberances — one 

 gastric, one cardiac, and two branchial. Gastric and cardiac pro- 

 tuberances more or less triangularly pyramidal; branchial protuber- 

 ance armed with an acute ridge running obliquely to postero-lateral 



