BY K. J. TILLYARD. 729 



hot sandy patches. It has a swift, dodgiDg flight, and on hot 

 summer days individuals may be seen chasing each other cease 

 lessly in and out of the river banks. The colours are black and 

 yellow, which in the very mature insect turns more to olive-green, 

 especially on the thorax. The appendages of the male are 

 yellow, subconical, with a large cornute tubercle or branch 

 underneath. The female carries, behind the occiput, three 

 tubercles of nearly equal size. 



15. AusrROGOMPHUS OCCIDENTALIS, n.sp. 



(Plate XXXV. figs. 5-6; Plate xxxvi. fig. 3). 

 (J. Total length 45 mm.; abdomen 34 mm.; forewing 27 mm.; 

 hindwing 26 mm. Wings: Neitration black, costa pale 

 greenish outwards; bases of wings very slightly saffroned. 

 Pterostigma large, broad, nearly 3 mm. long, rich brown between 

 black nervures. A minute yellow spot at the base of each win<y. 

 Nodal Indicator |11-14 7-10| Head: Occipital ridge 1mm., 

 yellow, suture I 9-10 8-IOI next the vertex brown and hairy. 

 Vertex black, with a round yellow spot behind, next occiput. 

 Antennce black, a fine yellow line on the inner side of bases. 

 Front greenish-yellow, a dull clouded brownish triangular area 

 above in the centre, and a dark brown or dull black band (of 

 varying width, according to the specimen) along the clypeal 

 suture. Clypeus yellowish-grey, sutures tinged with brown. 

 Lahrum and labium grey; genoi pale greenish-yellow; mouth 

 ^dged with brown. Thorax: Prothorax rather large, dark 

 brown, a small yellow mark on the collar in front; a double 

 small round dorsal spot, a larger spot on each side, and a small 

 spot touching the procoxa on each side, all greenish-yellow. 

 Meso- and metathorax rich brown above, a pair of fine slantin» 

 lines in front along the collar, behind these a pair of short ante- 

 humeral bars, somew^hat slanting, and a pair of spots near the 

 fore wing-joins; all these markings yellow more or less tinged 

 with green. Also a very fine yellowish line along the dorsal 

 ridge, only conspicuous for about 0-5 mm., where the ridge stands 

 up into a small spine tipped with brown. The sides are of 



