OBUSTACEA. 233 



smooth. Front 8-lobed, the lobes rounded, the median scarcely 

 more prominent than the rest ; the fissure between the median lobrs 

 and between the second and third lobes narrow-linear, those between 

 the first and second and the third and fourth loins triangulate. 

 Antero-latcral margins armed with six teeth, whereof the first is 

 subtruncated, the second to fifth triangulate and acute and directed 

 forward, the sixth about twice as long as the preceding and laterally 

 projecting. Chelipedes short and robust, arm or merus-joint with 

 two strong spines near the distal end of its anterior margin, its pos- 

 terior margin convex, smooth, and angulated at a point midway from 

 either extremity ; wrist with a strong spine on its inner margin, and 

 three smaller spines on its outer surface ; palm with three spines, 

 whereof one is situated at the proximal end close to the articulation 

 •with the wrist, and two on the upper surface ; there is none above 

 the base of the mobile finger ; the carinse of the upper and outer sur- 

 face of the palm and the intervening parts are nearly smooth ; the 

 fingers are armed along their inner margins with triangulate teeth, 

 which fit closely between one another when the fingers are closed, 

 and which are themselves divided into several smaller teeth. The 

 second to fourth ambulatory legs are slender, smooth ; the penulti- 

 mate joint of the fifth leg is not denticulated on its inferior margin ; 

 there is a sjjine at the distal end of the inferior margin of the 

 merus-joint. Length of the carapace of the largest example about 

 | inch (19 millim.), breadth to base of lateral epibranchial spines 

 about 1 inch (25 millim.). 



A single specimen is in the second collection, a male from Port 

 Darwin, 12 fins. 



There are in the British-Museum collection several specimens of 

 what is probably a mere variety of this species from Karachi 

 (Karachi Museum), referred to by A. M. -Edwards as G. callianassa, 

 which differ in having wider fissures between the median and the 

 second and third teeth of the front. The first tooth of the antero- 

 lateral margins is more distinctly truncated, and the last spine is 

 shorter ; also the spines of the arm, wrist, and palm of the cheli- 

 pedes are much shorter, those of the upper surface of the palm being 

 reduced to mere spinules, and the palm itself much more turgid, as 

 in A. Milne-Edwards's description. 



74. Goniosoma spiniferurn. (Plate XXIII. fig. C.) 



A single specimen is in the collection, obtained at Port Molle, 

 between tide-marks (Xo. 103), which is evidently nearly allied to, 

 and in M. A. Milne-Edwards's arrangement must be classed near to, 

 Goniosoma affine (Dana), from Singapore. It differs, however, in 

 the form of the frontal lobes, the median and submedian being 

 broadly rounded and separated by narrow and not deep fissures. 

 The fissure between the second and third lobe on each side is much 

 deeper, and, although narrow, wider than those between the median 

 and submedian lobes ; the third lobe is itself narrower than these. 



