INDIAN DRAGON FLIES. 927 



addition there is a fine humeral stripe incomplete above and below. 

 Beneath, the usual black, envelope marking. 



Wings long and broad, the reticulation very fine and giving a peculiarly 

 characteristic invisible appearance to the wings. Stigma of forewing 

 in the male distinctly larger than that of the hind, dark reddish brown, 

 whitish at the extremities (stigma of female distinctly larger than that of 

 male) ; a golden brown, basal marking in both wings extending about 

 halfway to the Ist antenodal nervure, not as far as the cubital nervure in 

 the forewing but well beyond it in the hind ; 8^ antenodal nervures ; 

 always 11 rows of cells between 5 and ba (quite occasionally there is only 1 

 row in other species of the genus) ; membrane blackish. 



Abdomen long and slender in the male, much stouter in the female, the 

 sides almost parallel and in the male, the internodal jouits distinctly 

 swollen. Black marked with yellow, each segment (except the yth, 9th and 

 10th in the male) bearing a long, oval, subdorsal spot. In the female 

 there is a small point of yellow on the 8th and two small spots of the 

 same colour on the distal half of the 10th. The sides of the first three 

 segments broadly yellow ; the ventral surface pruinose. Anal appendages 

 pale yellow with black tips in both sexes. 



Sexual organs : male : lamina broad and somewhat depressed ; external 

 tentaculas short, internal short, backvvardly directed, robust hooks; lobe 

 very slightly arched, small and very narrow, yellow. Female as in all 

 species of the genus, the borders of the 8th segment not dilated ; vulvar 

 scale small and inconspicuous. 



Pallidinervis has a distinct facies of its own which at once separates it 

 from all other members of the genus. With the exception of the small 

 lobe to the prothorax and the contracted discoidal field, there are few 

 features which place it as a trithemis. The differences between it and 

 other species may be briefly summarised and are so many that palhdinervis 

 might well be given generic rank. 



a. The insect is much larger than all other species of tritlwmis. A 

 moderate sized pallidinei vis may be as much as 20 mm. greater in expanse 

 than a small aurora, or 15 mm. greater than kirbyi, or 11 mm. t}\a.nf estiva. 



b. The difierences between the sexes is almost negligible when compared 

 with those of the other species, in fact it is much less than the difierences 

 between teneral males and adult females. 



c. The legs are characteristically long and spidery, the hind reaching 

 far beyond the hind border of the hindwings. 



d. The hind femora have a row of closely-set spines that are of even 

 length and there is a single longer spine at the distal end of the femora. 



e. The mid femora have a row of widely-set, gradually lengthening 

 spines. 



/. The armature of the hind femora in the female is exactly the same 

 as in those of the male. 



g. The wings are relatively very long and characteristically clear and 

 diaphanous. 



h. The stigmata in the wings of the male dift'er in size. 



I'll' 



Pallidinervis and kirhyi represent the two ends of the scale ui the chain 

 of evolution, the former being the most highly developed, the latter very 

 occasionally presenting archaic characteis. 



Hab. Locally throughout India. Poena, Bombay, Deesa, Thibet, 

 Ceylon, Madras. 



The insect is generally found perched high up on the summit of tall 

 reeds, beds of bull-rushes being a favourite site. It is peculiar in this 

 habit and therefore generally a solitary insect. The long, spidery legs are 

 bunched together and fully extended, so that its body appears stalked to 



