434 P. CAMERON. 



abdomen. The abdomen sessile, flat, the first segment 

 short, the second very large, more than twice longer than 

 wide, the last segment is large, as large as the preceding 

 three united, bluntly rounded. The penultimate ventral seg- 

 ment is projected backwards as a large triangular incision, 

 between which lies the hypopygium filling up the incision, 

 the ovipositor lying in the middle. Hypopygium large, 

 bluntly rounded at the apex. Stigmal branch curved, not 

 dilated at the apex, about two-thirds of the length of the 

 marginal branch ; the humeral branch is thickened at the 

 apex ; post-marginal vein twice the length of marginal. 



The malar space is two-thirds of the length of the eyes ; 

 the occiput roundly, deeply incised ; the base of the pro- 

 notum is roundly triangularly narrowed in the middle. The 

 head, thorax and abdomen are strongly punctured, almost 

 reticulated, in places umbilicately punctate. 



The anterior ocellus is clear from the frontal depression. 

 Hind tibiae with two apical spurs. Basal half of middle 

 tibiae narrowed. 



A genus readily known from all those hitherto described 

 by the greatly elongate triangular scutellum and second 

 abdominal segment. 



18. Heimbra acuticollis sp. n. 



Rufous, the sternum and metathorax black, the head, mesonotum 

 and back of abdomen more or less irregularly marked with black ; the 

 antennas rufous, or with the basal half black. Head, thorax, and ab- 

 domen umbilically strongly punctate, the scutellum more strongly than 

 the mesonotum, and the abdomen less strongly and with the punctures 

 running more into reticulations ; the basal slope smooth, margined 

 round the top and sides. Legs of a brighter red color than the body. 

 Wings hyaline, the nervures black. 9 . Length 4 mm. 



Head, thorax and legs covered with short white pubescence ; the 

 abdomen is more shortly and sparsely haired. The apical slope of the 

 metanotum is smooth, obliquely sloped and furrowed down the mid- 

 dle. The last ventral segment roundly bluntly projects, the projection 

 clearly separated above. The scutellum is more densely covered with 

 white hair than the mesonotum ; its apex bears longer hair. 



Mendoza, November. 



