382 



behind the middle, much wider at base than at apex ; anterior 

 angles strongly produced, acute and twisted ; sides sinuate in 

 front ; moderately widened behind middle, again converging 

 to the obtuse posterior angle ; margins strongly thickened and 

 raised almost vertically, concave within; apical and basal mar- 

 gins narrow ; disc closely set with moderately large punctures, 

 and two fovese near the centre, with no indication of a middle 

 line. Scutellum widely triangular, coarsely punctate. Elytra 

 ovate and convex, of same width as prothorax at base and twice 

 as long, shoulders rounded; sides widening to behind the 

 middle, then rather rapidly converging, but separately rounded 

 at apex; each elytron with three (besides a short scutellary 

 one) shining, wavy costae, the scutellary costa meeting the next 

 at base, the second also continuous to the base, the third ter- 

 minating on the shoulder ; with irregular transverse vermicu- 

 late ridges; the suture also slightly raised and, with the costae 

 and ridges, distinctly punctate, the interspaces and depres- 

 sions with punctures of unequal size. Whole under-side and 

 legs densely and rather coarsely punctate, the punctures 

 largest on the meso- and metasternum, finest (but very dis- 

 tinct) on the epipleurse and legs ; prosternum evenly convex, 

 its process rounded at apex. Dimensions — 17 x 8 mm. 



Hab. — Queensland: Marmor district (?) (H. Brown). 



A single specimen given me by its captor differs from the 

 other species markedly in its entire, thickened, and strongly 

 revolute margins to prothorax, with its surface more finely 

 punctured, its truncate base without any dentation or sinua- 

 tion, its thicker elytral costae (themselves distinctly punctate). 

 The form of the prothorax is somewhat as in Byallius reticu- 

 latus, Pasc, but the margins are much thicker, the anterior 

 angles more prominent, and the body is more convex than in 

 Byallius. 



Ononyctus, n. gen., Nyctozoilirarum. 



Head and thorax as in Byallius; mandibles bifid, mentum 

 cordate ; labrum emarginate and ciliate, displaying mem- 

 branous hinge ; apical joints of all palpi widely securiform ; sub- 

 mentum as in Nyctozoilus; intercoxal process widely and rather 

 squarely arched, its border carinate; prosternum convex, its 

 process rather flat, sulcate, and bordered at sides, rounded and 

 very little produced downwards at apex; mesosternum with 

 wide but shallow notch for its reception; epipleurae narrow, 

 with square f oveate impressions ; femora smooth ; tibiae without 

 line of tomentum, but scantily and shortly pilose ; posterior 

 tarsi wanting ; elytra coarsely punctate-sulcate ; rest as in 

 Byallius. 



