I9I5] 



Fauna of the CJiilka Lake : Crustacea Decapotfa. 



269 



The teeth on the rostrum are more variable m number than is indicated in the 

 description given by Henderson and Matthai. On the upper margin there are from 

 9 to 12 (usuahj" 10 or 11) and on the lower margin from 3 to 5 (usually 4). In all 

 cases the three posterior dorsal teeth are situated on the carapace. 



The measurements of a series of males are shown below. Of these specimens, 

 nos. I — 16 are fully developed, — that is to say, they have assumed the characters 

 typical of large individuals of their sex. The second peraeopods or chelipedes 

 are usually unequal in length and the larger of the two is nearh' equal to, or con- 

 siderably longer than, the total length; the segments are clothed with a fine velvety 

 pubescence and tubercles are present on the fingers on either side of the cutting edge. 

 With these features a well marked colour distinction is correlated, the chelipedes 

 being dark blue-grey with a pale dorsal stripe. 



In specimens nos. 17-22 the chelipedes are equal, or nearly so, and there are no 

 tubercles on the fingers. In nos. 17 and iS an inconspicuous pubescence, sparse and 



