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464 



Memoirs of the Indian Museum. 



[Vol. V, 



three pairs of legs in male having the merus and carpus dilated ; the first pair having a 

 small narrow process at the distal end of the propod. The terminal segment has the 

 middle part of the posterior extremity produced into a subacute point ; the postero- 

 lateral angles are long and very acute ; the inner angle of the notch for the insertion 

 of the uropod is quadrate and has another quadrate angle near it. 



Female differing from the male in having none of the joints of the anterior legs 

 dilated and in the absence of the process on the propod of the first pairs, also in hav- 

 ing the side-plates of segments 2, 3 and 4 separated from their segments by a distinct 

 suture. 



Length of body of largest male examined, 22 mm.; breadth, 11 mm.; length 

 of antennae 20 mm., length of uropoda 12 mm. 



Colour, slaty grey. 



In Miss Richardson's key of the American species of the genus Ligia, L. exotica 

 is placed next to L. baudiniana , which is distinguished from it mainly by having the 



Ligia exotica, Roux. 



Fig. 5. — Right mandible. 



Fig. 6. — Left mandible. 



propod of the first pair of legs unarmed, and in having the merus and carpus fur- 

 nished with a row of stiff hairs or bristles. The two species certainly seem to have 

 many points in common, and, as I afterwards state, it may be difficult to find char- 

 acters that will distinguish between them in all cases. L. exotica also seems to come 

 close to L. italica, Fabr., which appears to be distinguished, however, by the shape 

 of the posterior border of the terminal segment. I am not acqainted with any special 

 description of the male of L. italica, and the few specimens in my collection are too 

 small and immature to show the characters of the adult male. 



In addition to this short diagnosis, the following fuller description of the Lake 

 Chilka specimens may be given. 



The head is short and broad ; breadth 5 mm. and length 2*5 mm. It is regularly 

 rounded in front and the whole of the lateral margins and a portion of the anterior 

 margin are occupied by the large, rounded eyes which are separated in the centre by 

 a distance less than, the length of each eye. The part of the eye nearest to the 

 median line is rectangular with the angle rounded and not acute as in L. novae- 



