BORNEAN DRAGON FLIES . 



227 



Legs yellowish white, the joints, spines, .and a line on the 

 femora black. 



Abdomen : Segment 1 yellowish white with dorsal brown spot ; 

 segments 2-7 brown, becoming darker posteriorly, with narrow 

 black apical rings, 2 has a small pair of basal lateral blue(?) 

 spots ; segment 8 is black above, yellowish white below, 9 and 10 

 yellowish white. During life the light colouring on these seg- 

 ments is probably blue ; 9 and 10 have fine black basal rings. 



Anal appendages yellowish brown (? blue) tipped with black. 

 Upper pair a trifle longer than lower pair, each with a large 

 triangular projection inwards and downwards, scarcely visible in 

 profile. Lower pair cylindrical, slightly incurved, and with a 

 distinct elbow at the middle. (Text-fig. 6.) 



The presumed female of this interesting species has most un- 

 fortunately been completely destroyed whilst in my possession. 

 I have, however, in my possession an account of the specimen 

 which I append here. 



Colouring in general very similar to that of the male. It 

 differs as follows : — 



1. Antehumeral band of thorax completely divided by the 



black projecting mark into a broader lower part, which is 

 rounded below and pointed above, and a narrower upper 

 part, which is linear. 



2. Abdomen : Segment 1 entirely yellowish brown above ; 8 



pale above (probably blue during life); 9 black, with a 

 pair of pale marks above on either side of the middle line ; 

 10 black. 



The structure of the proihorax is very remarkable. A curious 

 crescentic projection stands out on either side of the middle lobe 

 attached to the pro thorax by its convex border. When looked 

 at obliquely from above, each of these projections shows like the 

 moon at the end of the first quarter, but when viewed directly 

 from above each shows as a single outstanding spur. 



In addition the black posterior margin of theprothorax carries 

 a fine black spur mid-dorsally. This is nearly -5 mm. in length, 

 and projects forwards and upwards at an angle of about 45° to 

 the long axis of the body. On either side of this projection lies 

 a small lappel, also black, directed backwards. 



I do not know of any structure in the Legion Platycnemis 

 that can be compared to the crescentic structure on the pro- 

 thorax, except in the females noted below. 



This female was taken in the same locality as the male, and 

 the two specimens were captured on two consecutive clays. They 

 agree in size and wing-characters, and closely in colouring, though 

 in this respect they are by no means identical. The evidence 

 that they belong to the same species is not conclusive, though 

 enough to justify the assumption that they may do so. 



Type S in the British Museum. 



