80 Bulletin Vanderhilt Marine Museum, Vol. V 



Material examined : One male, Pago Pago, Samoa, September 2, 

 1931, by the "Alva." 



Technical description: Carapace trapezoidal, very wide anteri- 

 orly, twice the length ; the posterior width about equal to the length ; 

 the interorbital margin very wide, the orbits occupying the antero- 

 lateral angle. The true frontal margin is equal to slightly more than 

 one-half the maximum width and is minutely bifid in the median line, 

 consisting of two very wide truncated submedian teeth, separated by 

 a narrow, button-hole like sinus from the outer pair of frontal teeth 

 which are similarly truncated distally, with the outer lateral margin 

 rounded, and separated by wide unequal-sided V-shape sinus from the 

 preorbital angle which is about one and one-third times as wide as the 

 adjacent frontal tooth, with its inner angle obliquely truncated, the 

 distal margin truncate and not quite as far advanced as the frontal 

 margin. The outer angle is slightly more than a right angle. The 

 orbital margin is wide, cut by two shallow sinuses; the postorbital 

 angle is an acute brown-tipped spine, which extends outward about 

 two-thirds the depth of the cornea. The lateral margins are decid- 

 edly convergent and bear two additional acute spines, successively 

 decreasing in size posteriorly. The posterior margin is notched above 

 the bases of the fourth and fifth pairs of legs and very slightly sinuate 

 in the median region. The dorsal surface is slightly convex fore and 

 aft and has three transverse granulate ridges, the anterior of which is 

 a slightly curved are with the ends pointing backward across the ante- 

 rior gastric region, and extending about as wide as the frontal margin ; 

 the second transverse ridge is a little longer, very slightly curved for- 

 ward and extends across the median gastric region ; the third ridge is 

 sinuate, extending inward from the last lateral tooth, across the 

 branchial region and becoming vaguely confluent with the curved uro- 

 gastric groove. The regions of the carapace are not otherwise defined. 



The chelipeds are equal in the male, about two and one-half times 

 the length of the carapace, with the merus granulate along the upper 

 half of its lateral margin and armed along the distal half with four 

 acute, procurved, acute spines; the carpus is armed with an acute 

 strong spine at the inner angle, and three shorter, acute, subdistal 

 spines in transverse series across the upper and outer surface; the 

 propodus has the palm slightly longer than the merus, with the upper 

 surface elevated in a crest, consisting of a double series of spines in 

 longitudinal series, the inner line consisting of five and the closely 

 adjacent line consisting of three, one each opposite the distal three of 

 the inner series. There is also a proximal spine on the outer surface 



