338 Mil. ROBERT GURNEY ON 



a rather swollen base (fig. 7) ; but in place of the usual external 

 long seta there is, in all adults, merely a small finger-like 

 outgrowth. On the other hand, in all immature specimens two 

 setse are present of the usual form. A further difference is that 

 the ramus is not, as is usual in C. grandidleri, distinctly produced 

 dorsally. There is indeed a slight overhang, but it is scarcely 

 noticeable (fig. 9). With regard to the fifth pair of legs the 

 agreement is closer, but here the innermost spine of the basal 

 joint is very much shorter than the others, and the second joint 

 is smooth on its inner face (fig. 8). In the proportional length 

 of the spines on this leg my specimens a,gree more nearly with 

 C. laciniatus Van Douwe, which itself seems to me only a. variety 

 of C gi^andidieri. Brady's description of C. cingcdeiisis is too 

 incomplete to make any satisfactory comparison possible. 



DiAPTOMUS DOEiAi Richard. 

 Anuradhpura. Bare. 



DiAPTOMUS STRiGiLiPES Gurney. 



Anuradhpura — Baltring tank ; Mahintele. Abundant. 



DiAPTOMUS ANN^ Apsteiu. (PI. II. fig. 10.) 



Peradeniya pond ; Kandy ; Colombo Lake. 



Brehm has found that specimens from Kandy do not agree in 

 all respects with the description given by Apstein, the third joint 

 of the exopodite of 'the fifth foot in the female being clearly 

 distinct, and argues that the separation or fusion of this joint 

 is therefore not of great systematic importance. In all my 

 specimens this joint is separate, and Apstein ha,s found that 

 it is, in fact, distinct in his original specimens. The endopodite 

 of this leg in my specimens, as in Brehm's, is considerably shorter 

 than the first joint of the exopodite, and, in respect of length, 

 this joint seems to be very vai'iaWe. I have seen one specimen 

 (fig. 10) in which this branch was clearly two- jointed, but this is 

 evidently an abnormality. 



DiAPTOMUS VIDUUS, sp. n. (PL II. figs. 11-14.) , 



In a collection from the Snake's pool at Mahintele, among 

 large numbers of D, strigilipes, a single male Diaptomus was 

 found which appears to belong to an undescribed species. In 

 spite of very careful search I have found only the single 

 specimen, but it seems to me so distinct that it is best to 

 describe and name it. 



The body is slender and tapering anteriorly ; last segment of 

 the thorax with pronounced posterior angles bearing two small 

 spines on either side (fig. 11). Fourth abdominal segment 

 asymmetrical, being slightly swollen on the right side. Furcal 

 I'ami and setse of normal shape. The left antenna reaches, when 

 reflexed, to the end of the fourth abdominal segment. The 



