544 Memoirs of the Indian Museum. [Vol,. V, 



not distinctly marked off from the straight hind margin; the palm is armed with 

 two rows of about a dozen spinules each, between which the dactyl fits when closed ; 

 the dactyl is long and curved, with a rounded projection on the inner margin near 

 the base, separated from the base by a somewhat deep concavity. The inner margin 

 of the dactyl bears a number of minute spinules. 



The second peraeopod (figs. 8g, h) is a little shorter than the first, and its dactyl 

 is irregularly shaped, showing an enlargement on the posterior margin towards the 

 base. 



In the third, fourth and fifth peraeopods, the basal joint is well developed and 

 broad. In the fifth (fig. 8k) the anterior margin is convex and bears numerous 

 setules, the posterior margin is straight with the upper and lower corners broadly 

 rounded. 



The inferior margin of the three pleon segments (fig. 8/) is rounded anteriorly 

 and in the first segment bears 5 or 6 spinules, while in the second and third seg- 

 ments there are no spinules ; the posterior angle in the third is produced into a 

 subacute point and there are a few minute spinules on the posterior margin. 



The uropoda (figs. 8m, n, o) are of the usual shape. In the first (fig. 8m)- the 

 outer ramus bears spinules only at the apex, while the inner has them also on the 

 inner margin; in the third (fig. 8o) the peduncle is longer than the ramus and is 

 somewhat broadened so that the upper margin is convex and bears three spinules. 



The telson (fig. 8p) narrows to the distal end at which there is a narrow emar- 

 gination; each lobe bears spinules along the posterior part of its lateral margin 

 and at the extremity. 



The female is of about the same size as the male, though specimens bearing eggs 

 are often shorter than the largest males, and have the body rather less slender. 

 The second antennae are considerably shorter than in fully developed males, the last 

 two joints of the peduncle being much less elongated; in this respect the females 

 resemble the younger males. The differences in the first and second gnathopods are 

 described below. 



The first gnathopod of the ovigerous female (fig. 8e) has no process on either 

 the carpus or the propod. The propod is shorter than the carpus, being about two- 

 thirds its length and narrows slightly distally, so that there is no trace of any palm. 

 The spinules on the various joints are numerous and rather conspicuous. 



In the second gnathopod (fig. 8/) the basal joint is greatly broadened, so that 

 the anterior margin is very convex, the greatest breadth being about the middle of 

 the joint, the anterior margin bears numerous spinules; the carpus shows the shape 

 described by M. Weber, with the rounded or somewhat angular enlargement on the 

 posterior margin, and the broadly rounded lobe of the propod extends far beyond 

 the end of the diminutive finger. 



As the collection contained numerous specimens of various sizes, I have been 

 able to trace out some points in the development of the gnathopods of the male. 

 In very young specimens, about 6 mm. long, the first gnathopod is almost the same 

 as in the female (fig. 8q) y except that the carpus is slightly shorter in proportion to 



