1895.] 
A. Alcock — Carcinological Fauna of India. 
209 
long 1 as the carapace plus half the rostrum ; the fingers, which are hardly 
one half shorter than the short palm, are arched and meet only near 
their tips : in the female the chelipeds are rather more slender than 
the other legs, are only as long as the post-ocular portion of the cara¬ 
pace, and have nearly straight fingers that meet in the greater part of 
their extent. 
The second pair of legs, in both sexes, are considerably longer than 
the chelipeds and than any of the three last pairs : the dactyli of all 
the ambulatory legs are stout, recurved, and serrated along the posterior 
margin. 
In the Museum collection are numerous specimens of both sexes, 
from Ceylon and Mergui. 
Hyastenus Tiilgendorfii , de Man. 
Hijcistenus Tiilgendorfii, de Man, Journ. Linn. Soc., Zool., Yol. XXII. 1888, p. 14, 
pi. i. figs. 3 and 4. 
This species much resembles H. pleione, but is distinguished by 
the following constant characters :—the carapace is but faintly tuber- 
culated, and, in particular, there is no tubercle between the gastric and 
cardiac regions : the dactyli of the ambulatory legs are very strongly 
toothed, instead of merely serrated, along the posterior margin : in the 
male the rostrum is nearby two-thirds the length of the carapace, and 
the chelipeds are as long as the carapace and rostrum combined, and 
nearly as long as the second pair of trunk-legs, — this being largely 
due to the increased length of the palm. 
Carapace subpyriform, and, like the rostrum and legs, pubescent; 
the regions moderately well-defined. 
The gastric region is either quite smooth, or presents three faint 
elevations disposed in a triangle base forwards. There is a small 
tubercle near the middle of the intestinal region ; and a line of granu¬ 
lations along the boundary between the hepatic and pterygostomian 
regions, which line is continued backwards, along the side of the branchial 
region, to end at a distinct lateral epibranchial spine : there is also a 
more or less distinct line of granules on the dorsal aspect of the epi¬ 
branchial region. 
The rostrum consists of two divergent spines, the length of which 
in the male is nearly two-thirds that of the carapace proper, but is con¬ 
siderably less in the female. Basal antennal joint with the outer mar¬ 
gin sinuously curved. 
The trunk-legs have the surface somewhat uneven : the chelipeds 
in the male are much stouter than the other legs, and are as long as the 
