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The external maxillipeds reach almost to the apex of the antennal scales. In the three 

 specimens there is a small spine at the base of the 2°<i pair of thoracic legs, this spine has 

 not been described by Alcock. The legs of the last pair extend just beyond the middle of the 

 antennal scales. 



The carapace of the largest male is i8 mm. long, without the rostrum, measured near 

 the dorsal median line; the petasma, lo mm. long, is a little more than half as long as the 

 carapace. This length was indicated by Alcock (1. c. 1901, p. 17) as characteristic of the variety, 

 for in the typical species the petasma should be about a third as long as the carapace (without 

 the rostrum). 



The 1 1 specimens from Stat. 1 5 are all very young and nearly of the same size. The 

 largest male is 53 mm. long, the carapace, rostrum included, measuring 15,5 mm., and without 

 the rostrum 9 mm. The straight rostrum that is slightly directed upward and armed with 6 

 teeth in addition to the epigastric tooth, reaches almost to the far end of the 2'^'^ antennular 

 article; the conical denticle on the longer flagellum is well developed. One observes at either 

 side of the median carina of the 4'^ abdominal tergum a subcarina that takes its origin about 

 at one-third the length of the somite from its anterior margin and that reaches until near the 

 posterior margin; the anterior third part of this tergum is smooth, glabrous and shining, but 

 the rest of the somite is tomentose. The subcarinae of the 6"^ somite are also well marked, but 

 those of the 5* are indistinct. The petasma is already 4 mm. long and it is therefore that I 

 refer this male to the var. andamanensis, because I suppose that the described subcarinae of 

 the 4'h and 6"^ terga will disappear at a more advanced age. Another specimen fully agrees 

 with the described one, but the conical tubercle of the longer flagellum seems to be wanting 

 in the three other males; they are, however, referred to the same variety, because they agree 

 in all other characters. The females fully resemble the males, the subcarinae of the 4"> tergum 

 are distinct, and not only the subcarinae of the 5"^, but also those of the 6'^^ somite are 

 wanting. The thelycum resembles Alcock's figure 13 (I.e. 1906), but the posterior end of the 

 median j^art shows but a very small incision. The two females from Stat. 302 agree with the 

 described ones. 



The two females from Stat. 12 are little larger than the preceding; one has lost the 

 rostrum, in the other it is 5 + 1 dentate, the foremost tooth, very small, is situated close to 

 the tip but far from the penultimate, so that evidently some teeth are not developed. The 

 subcarinae of the 4"^ tergum are as in the preceding specimens from Stat. 15, those of the 

 5"^ are rather indistinct, but on the 6"i they are well marked. The thelycum has, however, a 

 somewhat different form, the median part being square-cut, without posterior incision; the lateral 

 incisions, characteristic of the thelycum of Pen. philippincnsis (Challenger Macrura, PI. XXXV, 

 Fig. 2") are, however, also wanting. 



It remained doubtful whether the 4 very young specimens from Stat. 5 1 also belong 

 to this species or not. 



All the thoracic legs bear an exopod. 



General distribution: East of North Andaman Island; off Port Blair, Andamans; 

 off Cape Comorin, and in the Andaman Sea (Alcock). 



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