i88 Records of the Indian Museum. [Voh. XVI, 



covered or discriminated. The males of the genus, so far as 

 Indian species are concerned, are better known and more easily 

 characterized than females. 



In addition to slight venational differences, which are noted 

 below, the males have as distinguishing characters colour and 

 the structure of the anal appendages. By the employment of 

 these characters it is possible to subdivide the genus with groups 

 which appear fairly natural. 



In the following table I have given a list of the males of 

 all species that I know of as occurring within the limits of the 

 Indian Empire : — 



A. Ab rises at level of Ac. 



I. Colouring more or less uniform, without any marked 

 pattern on thorax and abdomen. Lower anal 

 appcndag-es projecting backward about as far as 

 upper pair and in general directed upwards. 



(1. Upper pair cylindrical or digitiform, in some 

 species a little decumbent at the apex. 

 Excision of posterior dorsal margin of 

 segment lo of abdomen moderately wide, 

 about as wide as distance between upper 

 appendages. 



1. Large species, or length of abdomen 



'■'' c? 38 nim ; colour of abdomen 

 rich blue, wings slightly tinged with 

 yellow ... ... ... C. coeynleiint. 



sp. nov. 



2. Large species, length of abdomen in 



cj about 38 mm ; colour of abdo- 

 men olive-brown, wings not tinged 

 with colour. Upper appendages 

 nearly as long as segment 10, with 

 an inferior hook-like tooth at the 

 extremity. Lower appendages not 

 so long as but well separated from 

 upper appendages, directed as much 



backwards as upwards ... C, olivaceiiiH, Laid- 



law. 



3. Thorax olive-brown, abdomen scarlet- 



red ; lower appendages longer than 

 upper pair, incurved at the apex ; 

 abdomen about 32 mm. in length ... C. erubescens, Selys. 



4. Small species, length of abdomen 26-28 



nim.; colour of abdomen orange- 

 yellow. Lower anal appendages 

 larger than upper, directed upwards 

 and tapering to their apices ; exci- 

 sion of segment 10 small and shallow C. I'jtbiae, Laidlaw. 

 b. Upper anal appendages, seen from above, 

 inflated, nearly touching each other, with 

 small internal tooth; excision of segment 

 10 very wide, Colour of abdomen lemon- 

 yellow ... ... ... ... C. coroniaiide- 



lianiim (Fabr.). 

 IL (^ abdomen with strongly contrasted colour pattern. 

 Lower anal appendages at least half as long again 

 as upper pair; abdomen bright red, segments 4-7 

 black ... ... .,, ... C. cermorubellum 



(Brauer). 



