I9I4-] F- F. Laidlaw : Odonata. 347 



46. Argiocnemis aborense, sp. nov. (PI. xvi, fig. 7.) 

 I cf Dibrugarh. 



Length of abdomen 24 mm. 

 ,, hind- wing 16 mm. 



Post- nodal nerves 8-9 on fore- wing. 



Arculus placed well beyond the level of the second antenodal, 

 very sharply angled. Quadrilateral rather long, its upper side in 

 both fore and hind-wings about three-quarters the length of its 

 lower side. Pterostigma black, moderate, oblique, covering one 

 cell. 



Head, upper surface entirely black, save for a pair of nearly 

 circular post-ocular spots which are blue 



Prothorax, black above, with a very small blue spot at the 

 side of the posterior margin. 



Thorax, black above, with a blue-green antehumeral stripe on 

 either side ; laterally bright blue, with a black line along the 

 second lateral suture ; below whitish. 



Abdomen black, segments q, 10 bright blue with fine black 

 margins, 10 with a dorsal longitudinal black line; i, 2 are blue at 

 the sides, and have also a small blue dorsal mark anteriorly, and the 

 black is contracted suddenly near the hinder end of the segment 

 so that it has here only a fine median dorsal black line ; 3 

 and 4 have a fine lateral blue-green stripe running along the 

 anterior | of the segment on either side, broader anteriorly; 5, 6, 

 7 have a small lateral mark of the same colour at their anterior 

 ends. The lower half of the sides of 8 is bright blue. 



Legs, femurs black behind, whitish-grey in front, tibias and 

 tarsi yellow with darker articulations. 



Anal appendages black, upper pair about half the length of 

 segment 10, hooked downwards and inwards, compressed laterally ; 

 lower pair shorter, conical, tapering rapidly and directed upwards. 



The first of these species of Argiocnemis is closely allied to 

 A. lunulata, de Selys The most obvious difference is that in 

 A . obsaira segments 7 and 10 of the abdomen are black ; further 

 in 2 the blue at the sides of the segment forms ' lunules ' but these 

 are very small not merely separated by the dorsal ridge. The 

 upper pair of anal appendages are longer, and less incurved at 

 their apices than in de Selys' species, to judge by the figure of 

 these given b}^ Dr. Ris (1900). On the other hand A. aborense is 

 very distinct from an}^ of the described members of the genus, 

 which will prove to be a large one. I have at present several 

 unnamed species belonging to it awaiting description. 



47. Argiocnemis sp. 



I cf Dejoo, N. Lakhimpur, base of hills, Upper Assam 

 [H. Stevens). 

 An imperfect specimen, perhaps A. rubeola, de Selys. 



48. Argiocnemis lacteola, de Selys. 



3 d' cf , I 9 Dibrugarh, N. E- Assam, Abor Expedition, 

 17 — 21 x-n (5. W. Kemp). 



