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the groove, separating the subhepatic and pterygostomial regions and continued backward on 

 the subbranchial regions, joints it. The tvvo former of these regions are entirely glabrous, but 

 between the infra-orbital crest and the bases of the chelipeds a very dense toment is found. 

 The peduncle of the antenna touches the front and is partly concealed ; there is a wide gap 

 left between the front and the very small triangular infra-orbital tooth, that is directed 

 obliquely-outward. Laterally there is no wall to the orbit, but beneath the latter we observe 

 a well-defined infra-orbital crest, stretching from the basal joint of the antennae 

 laterally and backward beyond the anterior notch of the carapace, so that its total length is 

 twice the breadth of the orbit; on strong magnification this crest proves to be very minutely 

 transversely striated. In /:". politus the same crest occurs. 



The epistome is distinct, hirsute; its length in the median line, where it strongly projects 

 distally is about one-fourth of the width between the bases of the antennae. The lateral 

 margins of the buccal cavern are diverging distally. The external maxillipeds leave a rhombic 

 space between them ; the ischium is as long as the merus, but considerably broader, the inner 

 margin of the merus is straight, the outer somewhat convex and the carpus is inserted near 

 the antero-external angle. The exognath is nearly wholly concealed, very hairy and thick, 

 reaching a little way beyond the suture between ischium and merus, and as Alcock remarks, 

 destitute of a flagelluin. 



The abdomen of the d 1 covers all the space between the bases of the posterior legs ; 

 it is triangular and all the segments are distinct ; the penultimate segment is as long as the 

 terminal one, and the posterior margin of the former is twice as broad as the anterior margin. 



The chelipeds are sometimes markedly unequal, but more often they present no difference 

 in size, and they may be called wholly smooth and glabrous; the borders of the meropodite 

 are, however, faintly crenulate, the inner margin of the wrist, immediately before the articulation 

 with the arm, presents some granules, and in the middle of the inner surface of the palm we 

 observe (in the c?) two indistinct longitudinal rows, each consisting of three or four largely- 

 separated granules. The palm of the d" is very high, higher than long, somewhat compressed, 

 but not keeled, below ; the fingers are very widely gaping, slightly compressed; the fixed finger 

 is largely excavated in the proximal half of the inner margin, the clistal half begins with a 

 crenulate prominence and is crenulate in the same way up to the acute tip; the movable finger 

 is only slightly curved, the proximal third portion of the inner margin is smooth, then follows 

 a quadrangular and crenulate tooth, and the rest of the inner margin is likewise dentate. In 

 the 9 the chelae are much smaller and lower; the fingers are longer and fitting closely together, 

 with the inner margins regularly toothed, and the rest of the surface furnished with a number 

 of longitudinal striae, that are prominent near the tip, but are dissolved further backward in 

 rows of very small pits. In the cases, where the d" presents unequal chelipeds, ths smaller one 

 resembles that of the 9. Alcock already observed, that the inner angle of the wrist is obtuse 

 in the cT, but always distinctly prominent in the 9. 



The middle pairs of walking legs, which are the longest, are about twice the length 

 of the carapace. The meropodites are smooth for their greater part, but the hind margin is 

 crenulate and near the not particularly keeled anterior margin numerous spiniform granules 



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