126 



The cervical groove, as in GecarcAnucus, makes a comparatively long and 

 narroAv loop; the groove is deep-cut and broad, except in the transverse part 

 which bounds the mesogastric area posteriorly- — this part is finer and more 

 superficial ; as in Gecarcinucus, the main trend of the groove is rather anterior, 

 in the direction of the orbital angle than of the lateral border of the carapace. 



The regions are distinct and individually tumid : in the gastric region there 

 is the usual post-frontal groove, which bifurcates narrowly behind and is 

 prolonged anteriorly almost to the edge of the front; in the gastro- cardiac 

 angle of each epibranchial region an oval areola is more or less distinctly 

 marked off, and between these the two small prsecardiac facets are just 

 indicated. 



Front, like that of Gecarcinucus, a long, narrow, s(]uare-cut, strongly- 

 deflexed lobe, very little wider than the orbit ; its edge is smooth and is 

 broadly, but sometimes obscurely, bilobed. 



Orbits wide in their vertical diameter, their outer angle small, but denti- 

 form and subacute, and not separated from the lower border by anj'^ gap. 



Antero-lateral borders of carapace rather "full," longer than the postero- 

 lateral, well arched, rather irregularly crenate ; one of the crenations, not 

 specially distinguished in size and not much distant from the orbit, is the lateral 

 epibranchial denticle. 



Epigastric crests broad and low, distinct but far from prominent, usually 

 appearing rather as small, smooth, or roughened lumps than as crests ; lying in 

 line with the post-orbital crests. The latter are low, blunt, and indistinct in 

 their inner half, and are sharper — but usually crenulate or broken in their 

 outer half. 



In the adult male abdomen the length of the 6th segment equals or slightly 

 exceeds its distal breadth, the sides of the segment being convergent and 

 slightly convex ; the 7th segment, which is a good deal longer than broad, is 

 contracted and broadly-rounded distally from a broadish base. 



The antennal jjeduncles loosely fill the broad orbital gap ; the flagellum is 

 short. 



The edge of the epistome is deeply festooned and slightly everted, so that, 

 as in Gecarcinucus, the efierent branchial openings are subtubular. 



The mandibular palp, as in Paratelphusa and Gecarcinucus, is two-jointed 

 (the first two joints being indistinguishably fused), and has the terminal joint 

 bifurcate from the base, the two lobes embracing the edge of the incisor process 

 of the mandible. 



The exopodites of all the maxillipeds have a strong flagellum. In the 

 external maxillipeds the exopodite is longer than the ischium, the ischium is 

 grooved, and the merus is subquadrangular antl hardly broader than long. 



The chelipeds in both sexes are imequal ; the merus has a squamiform 

 sculpture ; so has the carpus, but here usually it is more indistinct, and is 



