RATHBUN: CRABS FROM THE MALDIVE ISLANDS. 135 



The orbital margin is prominent, above finely crenulate, on the outside fluted 

 and denticulate. The postorbital constriction is strongly pronounced. 



The hepatic region is well marked off, its margin is sub-rectangular, with 

 two or three shallow teeth. 



The branchial region has on the antero-lateral margin 6 teeth with finely 

 crenulated edges, and on the postero-Iateral margin about 4 irregular lobes. 

 The blunt tooth or spine at the extremity of the branchial ridge is the most 

 elevated point of that region, but the carapace is widest at the first tooth out- 

 side the ridge. 



Posterior margin subentire. 



The chelipeds in the adult female are one and a half times as long as the cara- 

 pace, and unequal. The inner and outer margins of the arm are each bordered 

 by about 8 irregular lobes, of which 2, one at the middle and one at the distal 

 end of the outer margin, are the largest ; upper surface with one tubercle and 

 a few granules in a longitudinal series. 



The surface of the wrist is rough ; there is a prominent lobe at the middle of 

 the outer margin ; a tubercle on the inner margin. 



The upper surface of the hand has 2 strong laminate lobes near the wrist, 

 the outermost pointing backward and outward, the innermost further from 

 the wrist and directed forward and inward. The inner and outer surfaces 

 are crossed by an obliquely longitudinal line of tubercles of which 2 or 3 are 

 enlarged. Otherwise, except for a few granules, the surface is smooth and punc- 

 tate. Lower margin of arm and hand denticulate. 



The fingers are somewhat gaping when closed, in the larger cheliped, their 

 extreme margins, as well as a carina on the outer surface are granulate ; the 

 proximal half of upper margin of dactylus denticulate ; occludent margins 

 dentate, 3 large teeth on the poUex of the larger claw. 



The amljulatory legs increase in width from the first to the fourth ; the 

 first is very slender and about as long as the carapace, and has a few tubercles 

 on the margins, most noticeable on the margins of the merus and the lower 

 margin of the propodus. The second is a little shorter and stouter, with 

 larger tubercles. The third and fourth are bordered by laminiform lobes. 

 The dactyli of all the legs are long, slender, and pubescent. 



Dinunsions. — Female with ova: Length of carapace, 10.6 mm.; width, 

 10.9 mm. 



Type locality. — Nallandu, 24 fathoms, at anchorage, January 18 ; one 

 female with ova. 



Allied to L. confragosus Caiman, from which it is readily separated by the 

 strongly upturned branchial angles, the absence of a spine behind the cardiac 

 spine, the wider hepatic lobe, and the presence of only one lobe on the upper 

 outer margin of the hand. 



