56 MR. F. F. LAIDLAW ON 
The individual here recorded shows well the generic characters 
tabulated by Williamson. The wing characters are almost 
identical with those shown in his figure (loc. cit. fig. 27). 
A difference which may be merely individual, but if not, 
one that I should regard as of specific importance, is that the 
anal triangle of both hind wings of the Bornean specimen is 
divided into two cells only, by a cross-nerve running parallel to 
the long axis of the wing. Williamson’s figure might well have 
been taken from this representative specimen from Borneo 
excepting for this, for the difference in the number of antenodal 
and postnodal nerves, and for the fact that in the Burmese 
specimen figured the area included between Cu, and A, in the 
hind wing is a little shorter and broader than in the individual 
under consideration ; and, lastly, for a slight difference evident 
in the relative size of the pterostigmata. 
Details are as follows :— 
Length of abdomen 28 mm. 
Length of hind wing 28 mm. 
Venation :— 
13—12 9—9 
An.n. = Pn, ——- 
9—8 8—10 
Pterostigma a shade longer and narrower than in the type of 
the genus, covering 4 cells in the front wing. 
Head: Anterior surfaces black, with a rectangular yellow mark 
on either side of the upper lip, and a yellow spot at each angle 
of the lip; a transverse yellow band along the crest of the frons 
divided by a fine median line into two lateral halves. 
Thorax black above, marked with a yellow mesothoracic half- 
collar interrupted in the middle line, tapering laterally. A pair 
of narrow dorsal stripes of the same colour, not reaching to the 
base of the femora; a very small superior antehumeral spot on 
either side. Laterally, from immediately behind the humeral 
suture, the thorax is yellow marked with a black line which rises 
below at the level of the first lateral suture, includes the stigma, 
curves backward to join a second black line which follows the 
course of the second lateral suture, but bifurcates above to enclose 
a small yellow space. 
Abdomen black marked with yellow; 1 with a lateral spot on 
either side; 2 with a dorsal triangle, its apex directed backwards 
covering the first two-thirds of the segment, sides including the 
auricles also yellow ; 3-7 each with a fine yellow, basal, transverse 
mark dorsally, occupying about the first eighth of the length of 
the segment; 8 entirely black; 9 with the trace of a yellow ring 
at its apex; 10 entirely black. 
Legs black, the first pair of femora yellow on their inner side, the 
second pair with a small yellow mark on the same surface distally. 
Appendages black. The genital structures on 2 are almost 
identical with those shown in Williamson’s figure (Williamson, 
loc. cit. fig. 28.c), the second pair of hamuli not quite so prominent. 
