268 J. G. DE Man : Caridina nilotica. [Vor.. II, 



According to my original description in Max Weber's Zoolog. 

 Brgebn. einer Reise in Niederl, Ost-Indien, ii, 1892, p. 393, pL 

 xxiii, figs. 29 and 2()e, according to Schenkel (Beitrag z. Kenntniss 

 der Dekapoden-fauna von Celebes, 1902, p. 498) and also accord- 

 ing to Bouvier {I.e., 1905, p. 73), the rostrum of the var. gracilipes 

 is characterised (i) by the proximal row of the upper edge consisting 

 of 12 — 20 teeth, the usual number being 15 — 17 (de Man); (2) by 

 the occurrence, usually, of one subapical tooth, rarely two ; (3) by 

 the unarmed terminal part being longer than the proximal row, or 

 just as long, or rarely shorter, but in the latter case the proximal 

 row of teeth is no more than twice as long as the unarmed part. 

 Schenkel, indeed, remarks about the rostrum : " meist ungefahr 

 die Halfte, seltener nur ^ des Oberrandes zahnlos." In a single 

 specimen from the river Bonea on the island of Saleyer the upper 

 margin presented 24 teeth (de Man, I.e., 1892, p. 395), but this is, 

 no doubt, an exceptional case. 



The upper surface of the telson carries four pairs of spinules, in 

 some specimens five spinules were observed on one side and four 

 on the other ; the telson ends posteriorly in a very short tooth, 

 0'o6 mm. long, whereas the hinder edge itself, i.e.,t\\Q: linear distance 

 between the outer angles, is 0*35 mm. broad ; at either side of the 

 median tooth four spines are inserted, the first of which, at the 

 outer angle, is the shortest of all — 0"i2 mm. long ; the next spine is 

 the longest — 0*33 mm. ; the third and the fourth are subequal, the 

 third being 0'22 mm. long, the fourth, contiguous to the median 

 tooth, 0"2 mm. The telson of t5q">ical specimens of the var. gracilipes, 

 de M,, from Maros, Celebes, which are hang before me, fully agrees 

 with that of the Bengal variety. 



External maxillipeds reaching to the end of the antennular 

 peduncle. 



The legs of the ist and 2nd pair agree with those of the typi- 

 cal form from Egypt and also with those of the var. gracilipes. 

 The carpus of the 2nd legs presents a rather variable form : some- 

 times (No. i) it is very slender, as in the var. gracilipes, but in other 

 specimens, also adult, its shape is as stout as in the var. longirosiris 

 from Oran (egg-bearing female No. 3). 



The dactylus of the 3rd pair of legs (fig. 6), which is armed with 

 8 — ID spines, the terminal claw included, usually presents the same 

 slender shape as m the var. gracilipes, it being 4 or more than 4 times 

 as long as broad ; rarely, however, has the dactylus the same stout 

 shape as in the typical Car. nilotica from Egypt, so, e.g., in the 

 egg-bearing female No. 7, the dactylus of which is 3*8 times as long- 

 as broad. The meropodites of the 3rd legs are, in the adult 

 female. No. i, ten times as long as broad and armed with three 

 stout spines of equal length (o'26 — 0*27 mm.) ; the first is inserted a 

 little nearer to the proximal than to the distal extremity, the 

 second is as far distant from the distal extremity as the first from 

 the proximal, and the third is placed close to the distal extremity. 

 A similar spine occurs near the middle of the ischium and another 

 near the distal end of the lower margin of the carpus. 



