§0 Mr. H. W. Bates on the Longicorn Coleoptera 



catis, angulis externis vix dentatis : antennis nigris, infra parce 

 setosis, articulo quarto basi pallido. Long. 4| lin. 



Head tawny ochraceous, vertex with two oblique flexuous 

 dusky lines. Antennse black, two basal joints dingy ochraceous, 

 fourth with the basal third of its length pale testaceous ; they 

 are setose, but the basal joint beneath is free from setae. Tho- 

 rax on the sides tawny ochraceous, the middle blackish, with 

 two oblique S-shaped streaks converging in front on the fore 

 part of the disk ; the dorsal line is also dotted with ochraceous. 

 Elytra strongly narrowed towards the tip, which is not spined, 

 but obliquely truncated, with the sutural angle rounded off and 

 the external one simply acute; the surface is furnished with 

 rows of setiferous punctures ; there is no posterior carina, and 

 the colour is shining brown-black, with a sprinkling of tawny 

 specks, some of which collect to form two indistinct narrow 

 fasciae, one near the middle, the other near the apex. Body be- 

 neath dusky, with dingy ashy pile ; margins of ventral segments 

 whitish. Legs blackish ; claw-joints of the tarsi testaceous. The 

 apical dorsal plate has shortish and rather blunt teeth. 



Valley of the Irura, Santarem ; on dead boughs. 



Genus Oxathres, nov. gen. 



Body elliptical, moderately convex, setose. Anteunse fur- 

 nished with numerous setae. Thorax as in Probaiius, its outline 

 widening from the front to the tips of the lateral spines, which 

 are small, conical, and placed behind the middle. Abdomen in 

 the male with the apical dorsal plate notched or entire ; ventral 

 plate truncated and terminating in two stout teeth, like the 

 dorsal plate of Probatius. In the female the apical abdominal 

 segment is prolonged as a conical or short tubular sheath to the 

 ovipositor, the dorsal plate tapering into a very sharp point, and 

 in some species acutely carinated on its upper surface; the 

 ventral plate is simply truncated in the female. Legs moderately 

 short and stout ; thighs abruptly clavate ; tarsi short, even in 

 the hind legs, much shorter than the tibiae, but the first joint 

 slender and longer than the two following taken together. 



This genus, although closely allied to Probatius, is distin- 

 guished at once by the bidentation of the apex of the abdomen 

 existing on the ventral instead of the dorsal plate; but this 

 is seen in the males only, the females differing from the same 

 sex in Probatius still more widely — namely, by having an ex- 

 serted ovipositor and a prolonged pointed dorsal plate, instead of 

 a bidentated one. 



1. Oxathres navicula, n. sp. 

 0. ellipticus, rufescenti-fuscus vel obscure fuscus : thorace dorse 



