295 



the carapace are described as coarsely serrate, excepting the supra-marginal. In all the 

 present specimens, excepting the female from Stat. 31 2, however, the posterior moiety of the lateral 

 crest of the carapace, i. e. the middle one of the three at either side of the median dorsal 

 carina, ends anteriorly in a sharp tooth, directed more or less obliquely outward and forward, 

 and behind it there is but one small notch, while the rest of the moiety is smooth till the 

 posterior margin; the posterior moiety runs, in these specimens, straight backward, 

 parallel with its fellow at the other side of the carapace. In the adult female from Stat. 312 

 the posterior moiety of the lateral crest is slightly curved outward like in Fig. 3 of the 

 "Illustrations" and behind the anterior spine one observes three much smaller ones, of which 

 the posterior is placed on the left side nearly in the middle, on the right a little behind the 

 middle; also in the female without eggs from Stat. 306, of which the carapace is 11,5 mm. 

 long, measured in the middle line, on the left side traces of two, on the right side of three 

 minute prominences are found behind the anterior spine. 



In all the specimens the rostrum is bifid at the tip and the spine on either side at the 

 base seems to be larger than in the species from off Bombay. When the rostrum is examined 

 under the microscope, the triangular notch between the two minute teeth at the apex proves 

 to vary in form and size : in the ova-bearing female the notch is wide anteriorly, the inner 

 margins of the two teeth diverge distinctly forward, so that the teeth are easily perceived, when 

 only examined with a magnifying glass, but in other specimens, as e. g. in a male from Stat. 306, 

 the interspace is much narrower, the two teeth run here nearly parallel, close to one another, 

 and in such specimens the rostrum, when only feebly magnified, will often appear simple and 

 sharp-pointed, though being indeed bidentate. This is perhaps also the case in one of the three 

 Challenger types, in which specimen the rostrum has been described as "sharp-pointed" (St.\nley 

 Kemp, 1. c, p. 377). 



In the male the antepenultimate thoracic sternum is smooth, the two posterior 

 sharply carinated, in the female the three posterior thoracic sterna are smooth. In the 

 variety affinis, however, in the male the last three thoracic sterna are sharply carinated in the 

 middle line, in the female the carination of the antepenultimate sternum is distinct, but that of 

 the last two is obsolescent. 



According to Prof. Alcock's description the 2"'' pair of legs differ in the two sexes of 

 the species from off Bombay and we read here: "in the adult female they are almost as long 

 as the first pair, whereas in the adult male, and in the young, they reach but a very little 

 way beyond the carpal articulation of the hand". In the figure 4 of the "Illustrations", that 

 represents the male, the carpus of the 2'"' pair appears as long as the chela, but in the figures 

 3« and 3, of the female, one and a half to twice as long. In all the present specimens, however, 

 the 2"J pair of peraeopods (Fig. 70^^) differ not in the two sexes, reaching both in the male and 

 in the female but little beyond the carpal articulation of the hand. In the ovigerous female the 

 2"'' legs extend by two-thirds the chela beyond the carpal articulation of the hand of the anterior 

 legs, the carpus (2,8 mm.), which is 7-times as long as thick at the distal extremity, is one-sixth 

 longer than the chela (2,4 mm.); the dactylus, i mm. long, is but little shorter than the palm 

 and the greatest width (0,54 mm.) of the chela measures about one-fourth its length. 



