NO. 3 GARTH : SOME NEW SPECIES OF BRACHYURAN CRABS 57 



Description: Carapace strongly areolate and almost completely 

 coarse granulate, except the spaces between the elevations of the an- 

 terior portion, which are bare and microscopically punctate. Branchial 

 elevations extensive, rounded, and tumescent, inside of each a small, 

 triangular areole separated by a deep and naked furrow. Anterolateral 

 margin with sharp denticles grouped in threes, the center of each 

 projecting slightly beyond the others. Posterolateral margins indented 

 in a succession of four steps. Front little advanced, lobes broadened, 

 separated by a shallow depression which communicates with the gastric 

 region posteriorly. Other important areoles located as follows : epigastric, 

 gastric, postbranchial, cardiac, and lateral to the cardiac region. Pos- 

 terior portion of carapace most conspicuously and irregularly granulate, 

 the granules extending into the depressed areas between the areoles and 

 interspersed with short yellow hairs. 



Subhepatic region, external maxilliped, sternum, and abdomen 

 densely granulate. External maxilliped with granules arranged in rows 

 parallel to the long axis of the body, a conspicuous row of punctae 

 separating the two median rows on both ischium and merus. 



Abdomen and sternum of both sexes with numerous raised, berried 

 tubercles separated by deeply eroded pits. Terminal segment of female 

 abdomen triangular, sides almost straight. 



Tubercles of carpus and manus of cheliped arranged more or less 

 in rows, those of the superior crests sharpened. Granules extending to 

 tips of dactyls. The left cheliped is wanting in the type specimen. 



Ambulatory legs with laminate edges denticulate, their superior 

 surfaces paved with rows of granules extending even on the dactyls, the 

 tips of which are amber. Dactyls with paired inferior laminae. 



Color in life: Carapace cadmium orange with numerous light 

 blotches of madder brown scattered over entire surface. A large patch 

 of madder brown in median groove on gastric area. Eye pale greenish 

 black. Chelae as carapace on outer side, white on inner side. Granules 

 on movable finger madder brown fading gradually toward tip, which 

 is almost white. Fixed finger with a few light touches of cadmium 

 yellow. Ambulatory legs pale cadmium yellow, granules pale madder 

 brown, many of them white. (Petersen) 



Color in alcohol: The holotype, in spirit nine months at this writ- 

 ing, still shows spots of deep magenta in the depressions surrounding the 

 gastric and epigastric regions. 



Remarks: This species, closely allied to O. galapagensis Rathbun 



_. ILIGRAR Y) 



