420 Mr. R. M'Lachlan on some Odonata 



blackish, with no defined T-spot ; vesicle olive-green ; eyes 

 connected in a long space, occiput very small, slightly excised 

 on its margin, black; back of head shining black. Thorax 

 dark blackish brown, with black villosity and green markings 

 as follows : — a broad band on either side of the dorsal crest 

 interrupted posteriorly by the crest of the antealar sinus ; two 

 large interalar spots ; on each side two large oval bands or 

 spots, one under each wing, not extending to the legs ; pectus 

 brown. Legs black ; coxse, anterior and intermediate tro- 

 chanters, and anterior femora at base beneath brownish ; claws 

 red, tipped with black. Abdomen orange-red ; a very distinct 

 ring at the base of segments 2 to 7, segments 8 to 10 wholly 

 (excepting some red spots on 8) and a ventral line black ; at 

 the apex of each segment from 1 to 7 is a greenish ring with 

 indications of a narrower one on the transverse false sutures ; 

 margin of tenth segment above slightly excised in the middle 

 and with a fovea at the insertion of each appendage. Ap- 

 pendages black (broken) ; tenth ventral segment rounded, 

 denticulate, with 4 or 5 of the teeth much more prominent 

 than, and twice the length of, the others ; vulvar lamina with 

 black side-sheaths and strong reddish spine. 



Wings hyaline, very shining ; pterostigma small (4 millim.), 

 black; membranule whitish; neuration open, black; sub- 

 nodal sector furcating on a level with the pterostigma (slightly 

 before in posterior), the space between the branches com- 

 mencing by a single cellule, followed by two rows, and ending 

 in 4 or 5 marginal cellules; 5 or 6 cellules in the space 

 between the subnodal and the underlying interposed sector 

 in its broadest part ; no basal subcostal nervule ; 1 9 ante- and 

 15 postnodals in the anterior wings, 13 and 16 in the poste- 

 rior ; 4 supra-trigonals in the anterior and 3 in the posterior ; 

 5 cellules in principal triangle in anterior and 4 in posterior ; 

 5 nervules in the median area in the anterior and 3 or 4 

 in the posterior (excluding the nervule forming the inner 

 triangle). 



Length of abdomen {excl. append.) 59 millim. ; length of 

 posterior wing 55 millim., greatest breadth of same 17 millim. 



Hah. Sabathu, near Simla (N.W. India), July 1888, one 

 female. 



It will be necessary to see the male before attempting to 

 define the nearest allies of this magnificent insect ; the in- 

 equality of the teeth on the tenth ventral segment may be 

 significant. 



In this individual the abdomen had been " prepared " when 

 fresh by the extraction of the contents and the substitution of 

 cotton-wool, so that the colours are no doubt more vivid than 



