236 MAJOR F. C. FRASER ON 



azure blue with narrow, subapical, black annul es which are spined ; 

 segment 10, the dorsum bearing a large, quadrate, black spot. 



Superior anal appendages as long as the 10th segment, 

 strongly bifid at the apex, black, whitish internally, with a robust, 

 basal spur directed downward and inward. Inferior appendages 

 small, short, foliate, white with a minute apical, black point. 



Female unknown. 



This new species belongs to the group which includes Pseu- 

 dagrion bengalense, P.*microcephalum and P. laidlawi. From the 

 first it is distinguished by having black annules on segments 8 and 9, 

 and by the goblet on the dorsum of the 2nd segment not being 

 hollowed out in front and by the fewer postnodal nervures; from the 

 second by the fewer postnodal nervures and the dorsal marking on 

 the 2nd segment; and from the third by the ground colour being blue 

 instead of lilaceous, by the shape of the dorsal marking on the 2nd 

 segment which is shaped as a thistle-head in laidlawi, and lastly by 

 the superior appendage having a basal spine which is absent in 

 laidlawi. From P. williamsoni it is distinguished by the shape of 

 the marking on the 2nd abdominal segment. (Fig. 2. h). 

 24. Ceriagriox auranticum, sp. no v. 



3 males from Bangkok, Aug. 20. 21. 



Male. Length of abdomen 27 mm., hindwing 18 mm. 



This insect is very similar to two closely related forms : — 

 C. rubiae Laid., and C. erubescens Selys. 



It is to be distinguished from both by the shorter petiolation of 

 the wings, this ceasing distinctly before ac. In this respect it differs 

 from all other forms that I have had the opportunity of examining. 



The arc is also well distal to the 2nd antenodal nervure, 

 agreeing in this respect with erubescens, but differing from rubiae 

 in which the are lies opposite the 2nd antenodal. 



The ground colour is a much richer orange than in rubiae 

 and differs from erubescens in which the colouring of the abdomen 

 is crimson. 



The stigma is a warm, light reddish brown, almost brick red. 

 Postnodal nervures number 10 in the forewing, 8 in the hind. 



JOURN. NAT. HIST. SOC. SIAM. 



