450 P. CAMERON. 



femora not more swollen than the others. Fore tibiae with 

 one, the others with two spurs. 



The pronotum is nearly as long as the head, and is dis- 

 tinctly longer than the mesonotum ; there is a curved furrow 

 along the lower part of the propleurae. The first abdominal 

 segment is twice longer than the second ; the abdomen bears 

 no tubercles on the second segment. Tarsi longer than the 

 tibiae. Claws simple. 



Comes nearest to Dissomphahis, Ashm., which may be 

 known from it by the second abdominal segment being longer 

 than the first, and bearing two small, round, wart-like tuber- 

 cles, by the mandibles being quadridentate, and by the 

 anterior basal cellule being much longer than the hinder, and 

 gradually narrowed to an acute point, not wide at the apex 

 as in Ashmead's genus. Judging from Ashmead's figure of 

 Dissomphahis the scutellum is not much widened towards the 

 apex as it is in the present genus where it is narrowed as in 

 Isobrachium. 



36. Xestobetliylus pallidipes sp. n. 



Black, shining, the thorax more so than the head, and the abdomen 

 more than the thorax, the antennas rufo-testaceous, paler at the base, 

 the mandibles rufous, with black teeth ; the legs pallid testaceous, 

 much paler than the antennas ; abdomen rufo-testaceous. Wings very 

 clear hyaline, very iridescent, the nervures and stigma testaceous, the 

 costal cellule at the base of the stigma clearer than the rest, almost 

 white. Pro- and mesonotum with distinct, clearly separated punctures, 

 the scutellum very smooth and shining. Metanotum strongly acicu- 

 lated ; its central keel extends from the base to the commencement of 

 the apical slope. Upper part of the meso- and metapleurae smooth, 

 bare and very shining, the lower and the sternum opaque and bearing 

 shallow, distinct, cleariy separated punctures. Mesosternum bordered 

 by a fine furrow. 9 . Length 5 mm. 



Body and legs covered with a short white pubescence. Metatarsus 

 as long as the following joints united. Palpi testaceous. Apical three 

 abdominal segments infuscated at the base. Genital armature large, 

 prominent. Apical abdominal segments more prominent than the 

 others. The scutellum becomes gradually narrowed towards the apex. 



Mendoza, December. 



