TO INDIAN CAKCINOLOGY. 455 



288. Gonodactylus Demanii, n. sp. (PL XL. figs. 23, 24.) 



Gonodactylus, n. sp. ? De Man, Brock's Crust, p. 574, Taf. xxii.«, fig. 7 (1888). 



Rameswaram ; four females, two males (J. B. H.). 



I have pleasure in naming this species after Dr. J. G. De Man, who, in Ids Report on 

 the Crustacea collected by Dr. Brock in the Malay Archipelago, describes and figures a 

 single specimen from Pulo Edam, pointing out that it is probably new, but without 

 giving it a name. It is closely allied to G. chiragra, but the differences seem to me 

 other than varietal, and are not due to the specimens being young, for the following 

 comparison has been made with examples of G. chiragra of similar size, and from various 

 localities, in the British Museum collection. 



In G. chiragra the median of the three bosses or elevations on the dorsal surface of 

 the telson is always narrow and longitudinally oval, witli its distal end frequently 

 embraced by a horse-shoe-shaped or semicircular elevation, but without spinules. In 

 G. Demanii the central elevation is much broader, and indeed subglobular ; when viewed 

 in profile it is also seen to rise much higher above the level of the telson than in the 

 other species. A series of from five to seven spinules is placed at the distal end of this 

 elevation, usually arranged in a somewhat semicircular form, but there is no trace of the 

 semicircular elevation seen in G. chiragra, unless the spinule-bearing region represents 

 it. The narrow lateral bosses, which are not sufficiently defined in De Man's figure, 

 carry one or two spinules at their distal ends, and two or three spinules also occur at 

 the base of each of the two submedian terminal spines of the telson. None of these 

 spinules occur in G. chiragra, and in this species the four inner longitudinal and spinule- 

 tipped elevations on the sixth abdominal segment are subequal in size, or at most the 

 median pair are only very slightly larger, whereas in all my specimens of G. Demanii 

 the median pair are distinctly larger. The lateral processes of the frontal plate are more 

 acute than in G. chiragra, but this part appears to vary slightly in the latter species. 

 In all the specimens, round black pigment spots occur on the dorsal surface of the 

 hinder portion of the carapace, on the second free thoracic segment, and on the first, 

 third, fourth, and fifth abdominal segments; this may be a juvenile character, but in 

 similar-sized examples of G. chiragra the rnottlings, when present, are neither so well 

 marked nor so regularly distributed. 



The largest specimen, a female, is 23 mm. long, and the largest male 20-5 mm. ; but 

 the second male, although only 12 mm. long, has the sexual appendages developed. 

 De Man's specimen, a female, was 17 mm. long. 

 Distribution. Pulo Edam (De Man). 



Genus Protosquilla, Brooks. 

 289. Protosquilla trispinosa (Dana). 



Gonodactylus trispinosus (Dana), Miers, Ann. Mag. Nat. Hist ser. 5, vol. v. p. 14, p). iii. fig. 10 (1880). 

 Rameswaram (Thurston) ; Gulf of Martaban ; Ceylon (Brit. Jlus.). 

 Distribution. Mauritius (Hoffmann) ; West Australia and Amboina (Miers) : Auckland, 

 New Zealand (Setter); Eijis (Dana). 



