276 Bulletin Vanderbilt Marine Museum, Vol. VII 



the Gulf of California, while on the Galapagan, Panamian and 

 Chilean specimens, the setae of the third ambulatory is present 

 all over, as stated by Stimpson for his eriomerus; the present 

 series showing mostly short setae, which are spaced the same as 

 when they occur long. The fourth and fifth pairs of ambulatory 

 legs also have these setae on both the broad and narrowed upper 

 margins of the merus. 



Technical description: Carapace squarish, about as wide 

 as long, posterior- and anterolateral angles slightly rounded, a 

 distinct, deflected postorbital angle; the interorbital region tri- 

 angulate, deflected, showing quite a little variation in the degree 

 of prominence of the triangulate apex, likewise of the median 

 groove of this region. The cervical and hepatic grooves are dis- 

 tinct. The carapace is covered with low, granulose squamae, 

 weak anteriorly, nearly smooth or coarsely punctate on the 

 gastric and central portions, coarsely and usually regularly trans- 

 versely-obliquely striate on the branchial and lateral areas, these 

 striae being formed of continuous series of granules minutely 

 setigerous on their anterior margin. The linear lateral margin 

 is formed of a distinct beading of these granules. The normally 

 subequal chelipeds are large and continuously paved with these 

 granules, which when very abundant tend to form transversely 

 oblique rows along the posterior margin of the carpus and nor- 

 mally form a small marginal beading along the anterior lateral 

 margin, this more rarely bearing a few, irregularly distributed, 

 coarser, dentiform granules. The merus is trihedral, short, with 

 a blunted, knob-like process at the anterior distal angle; the 

 carpus varies in length, from nearly equal to its own width, to 

 one and a third, or more frequently one and three-fourths or 

 twice this width, with the lateral margins varying from parallel 

 in those specimens having the distal process reduced or absent, 

 to not so, the anterolateral margins diverging distally from the 

 postlateral margin in those specimens which have a prominent 

 laminate process at the anterolateral angle. The distal dorsal 

 margin of the carpus is trisinuate. The propodus and dactyl are 

 triangulate, large, the inferior lateral margin being relatively 

 straight, the superior margin diverging distally to the base of 

 the finger, where it unites with the slightly shorter, superior 

 margin of the dactyl, forming the apex of the triangle ; the supe- 

 rior margin of the dactyl converges distally meeting the inferior 



