181 



A specimen (fig. 95), in the National Museum, has the 

 prothorax narrowly but distinctly margined with black, so 

 that there appears a narrow pale stripe a short distance from 

 each side. Its elytra also have the dark markings more ex- 

 tended than usual, with the humeral spot continued as a stripe 

 almost to the apex, and connected with the sutural patch 

 near the apex and again near the scutellum, so that an 

 elongate, pale, irregularly-defined spot is enclosed on each side. 



The species is abundant in the coastal districts of New 

 South Wales and of Southern Queensland, and has a rapid 

 and noisy flight. Specimens are often seen and heard flying 

 through the suburban streets of Sydney and Brisbane. 



Diaphonia xanthopyga, Germ. 

 PI. xi., figs. 100 to 107. 



For this species the genus Melobastes was proposed by 

 Thomson, but it should never have been removed from 

 Diaphonia, in which it was allowed to remain, even by Kraatz. 



The species is subject to considerable variation in size( 38 > 

 (17-27 mm.) and markings, more especially in the female. 

 The type was evidently an ordinary male, but rather small 

 and with the scutellum entirely black (only three males before 

 me have the scutellum entirely black, in most specimens much 

 of it being pale). On specimens in good condition the margins 

 of the prothorax are usually paler (usually quite flavous) than 

 the disc, but with age the prothorax (except for such dark 

 markings as are present) tends to become uniformly reddish- 

 castaneous. But the narrow black basal edging is always 

 present, and the apex is also always narrowly black, at least 

 in the middle. Frequently a small vague dark spot can be 

 traced close to each margin, slightly in advance of the middle. 

 A small fovea may sometimes be seen on each side of the 

 pygidium; but it is usually not traceable. It may appear on 

 either sex. On fresh specimens some long reddish hairs may 

 be seen on the elytra, but they are usually completely 

 abraded. 



The female (apart from colour) differs from the male in 

 being wider, elytra less narrowed, prothorax more convex and 

 with more rounded sides/ 39 ) head slightly smaller, club of 

 antennae much smaller, abdomen evenly convex along middle 

 (instead of widely depressed), mesosternal process slightly less 

 prominent, and legs distinctly shorter, with the tibial denti- 

 tion more pronounced (many females, however, have the teeth 



(38) The type was nine German lines, not five, as quoted by 

 Kraatz. 



(39) The sexual variations of the prothorax and elytra are much 

 as in satelles. 



