SHORT NOTES. 191 
Orogomphus dyak, sp. n. 2 3 1 @ 
6 Hind-wing length 26 mm. ae np 
Abdomen (without appendages) 50 mm. Wings hyaline. 
. Upper and lower sides of discoidal triangle of hind-wing 
of equal length ; inner side a little shorter. Discoidal minal 
of both wings divided transversely into 2 cells; both followed 
by 2 rows of cells. 
3 nervules in basilar space of. both wings, 5 supra triangular 
nervules i in both wings. Anal loop contains 7 cells. 
19-21 antenodal, 11 post nodal nervules on front-wings. 
Anal area divided into 3 cells. | 
Colour. Black and yellow. 
Head. pada: eer 
Lower lip and palps yellowish. 
Upper lip entirely black. 
Nasus and rhinarium pale yellow. 
Frons and vertex black, the crest of the frons with a fine 
yellow line. Occiput black. 
Prothorax black marked with yellow. 
Thorax black, with a fine yellow anthumeral stripe one 
either side, and three lateral yellow stripes. 
Legs. Black, the first pair with yellow coxae, 
Abdomen. Black. 
Segments 1.2 with yellow lateral markings. Those 
on 2, covering the upper half of the small auricle 
and running up to the middle of the back of segment 
which has also a fine terminal yellow circle. 
The rest of the abdomen entirely black save for a terminal 
reddish yellow ring on the distant end of 6, broader above and 
appendages black, the lower one as long as the upper pair. It 
is rather quadrilateral with an indented terminal margin,. so 
that on either side it has a horn-like projection directed back- 
wards and curving a little upwards. 
R. A. Soc., No. 57, 1910. 
