392 PROCEEDINGS OP THE ACADEMY OP 



upper edge of the occiput straight, narrowly bordered with black, and ciliate 

 with long black hairs, its lateral margins behind generally black ; vesicle of 

 vertex loftily cariniform or laminiform, black, slightly abbreviated, a little 

 emarginate, almost truncate at its extremities ; region of the ocelli and vertex 

 black ; antennae black ; basal half of the superior surface of the front black ; 

 a broad medial black band on its anterior surface, straight above, below gene- 

 rally extending in two waves to the transverse striae on its anterior submargin, 

 which are unusually deep ; epistoma blackish ; labrum margined anteriorly 

 and sometimes laterally with black, and with a wide basal black triangle, 

 which is sometimes confluent with the black anterior margin ; tips of man- 

 dibles, central lobe of labium, and interior margin of its lateral lobes, all 

 black ; back of the head black, with two separate and distinct yellow spots 

 behind the eyes on each side. Prothorax black, with the middle of its ante- 

 rior edge, one small transverse double spot on its disk, one larger lateral round 

 spot, and one short oblique line immediately above the coxae, all greenish yel- 

 low; dorsum of thorax with a double medial black stripe, almost always 

 widened in front, not attaining the anterior margin by one-half to two-thirds 

 millimetre ; the dorsal carina yellow, except a small spot in front which is 

 black, and all behind its posterior furcation, which is black and narrowly 

 margined with black; the antealar sinus black in front ; a wide antehumeral 

 black stripe abbreviated above, and a humeral black stripe on the suture never 

 confluent above with the antehumeral ; pleura with a black oblique line, some- 

 times interrupted towards its upper end, just before the spiracle which is 

 black, and a narrower line in the suture behind the spiracle, which last line 

 is occasionally subobsolete ; sternum pale greenish, sometimes varied with 

 iusky, often with a large obscure dusky spot behind the posterior coxae. Ab- 

 domen black, expanded to an unusual width on segments 7 9, its dorsum 

 marked with greenish yellow as follows : Joint 1 with a large terminal obtri- 

 gonate spot extending to its base ; 2 with a broad vitta, generally bi- emarginate 

 laterally ; 3 7 with a narrow basal line tapering to a point behind, slightly 

 or not at all abbreviated in 3, more and more abbreviated towards 7, where it 

 reaches to only two-fifths of the joint, and is a little wider than in any of 

 the other joints ; earlets on joint 2 yellow, anteriorly black, posteriorly with 

 many minute black teeth ; laterally joints 1, 2 and 9 are yellow, except the 

 posterior edge of 2 ; 3 7 with a basal yellow triangle, extending to the infe- 

 rior margin ; 8 with a transverse basal yellow line on the dorsum, sometimes 

 invisible, which is in reality a membranous prolongation of 7, and also with a 

 large, quadrangular, basal, yellow spot, one third or one-fourth as long as the 

 joint, which never attains the inferior margin of the segment, though it always 

 attains the basal angle ; venter fuscous, sometimes mottled with yellow. Ab- 

 dominal appendages black ; the superiors wide apart at base, twice as long as 

 the last abdominal joint, which is one-quarter the length of the penultimate 

 joint, slender, conical, strongly divaricate, regularly curved downwards for 

 three-fourths their length, when they suddenly curve upwards and taper to a 

 very fine, long, acute point ; below at the change in the curvature is a small 

 spine directed downwards ; the inferiors are three-fourths as long as the supe- 

 riors, wide apart at base, more divaricate than the superiors, slender, taper- 

 ing, obtuse, suddenly curved upwards at three- fourths the distance to their 

 tips, with a deep obtuse stria on their external basal half. Legs black, coxae 

 generally more or less yellow exteriorly ; anterior femora with a broad poste- 

 rior yellow vitta slightly abbreviated, but never covering less than five-sixths 

 of their length. Wings hyaline, almost always slightly fiavescent at base ; 

 jostal vein anteriorly yellow to the commencement of the pterostigma, occa- 

 sionally only 'o the nodus ; the other veins and cross -veins black ; pterostigma 

 brown, sometimes yellowish brown, surmounting 4 5 cells ; membranule 

 cinereous. Antecubitals 14 15 ; postcubitals 10 13. Two discoidal areo- 

 iets, commencing generally with three ; occasionally with two in the upper 

 wing, tut never in the lower wing. 



[Sept. 



