BEACHTCISTIS. 401 



B, tysias approaches this species ; but it is larger, and has the antennae shorter 

 and stouter, and the body more pilose ; the petiole is longer and much more deeply 

 furrowed down the centre, especially towards the middle ; the furrow behind the 

 ocelli is wider and deeper ; the furrows on the mesonotum are deeper ; the area on the 

 base of the median segment is shorter ; the basal narrowed part of the petiole is 

 longer, and it has a distinct longitudinal furrow, which extends near to the apex, the 

 apical half is much more strongly punctured, and the hair is longer and thicker ; the 

 mesopleurse are much more strongly punctured, the metapleurae more deeply and 

 widely excavated. 



6. Brachycistis arines. 



Ferrugineus, capite nigro, abdominis apice fusco, antennis testaceis ; pedibus pallide testaceis, femoribus 



posticis fuscis ; alis hyalinis, nervis pallidis, stigmate fusco. c? . 

 Long. 10 millim. 



Hab. Mexico, Northern Sonora {Morrison). 



The head is somewhat narrower than the mesothorax, black, shining, very sparsely 

 haired ; abruptly narrowed behind the eyes ; the anterior ocellus with a semicircular 

 furrow in front, and from this furrow runs a short sharp keel ; the clypeus and mandibles 

 are ferruginous, the tips of the latter black. The antennae are longer than the head, 

 thorax, and petiole united, very little attenuated towards the apex ; the third joint 

 hardly longer than the fourth ; the apical joints slightly dilated on the underside. 

 The thorax is sparsely covered with short white hair ; smooth, impunctate ; the para- 

 psidal furrows reaching near to the base of the mesonotum ; the scutelhim smooth, 

 impunctate, glabrous, the furrow at its base deep. The median segment has a gradually 

 rounded slope, impunctate, with carinae or reticulations. The pro- and mesopleurae 

 are impunctate, sparsely covered with soft white hair ; the base of the metapleurae is 

 smooth, shining, and impunctate, its apex closely punctured. The petiole is somewhat 

 longer than the second segment and is gradually dilated towards the apex ; it bears 

 long fuscous hair and is obscurely punctured at the apex ; its lateral keel is distinct. 

 The other dorsal segments are impunctate, shining, for the greater part black, and are 

 sparsely covered with long white hair. The legs are testaceous, covered with long 

 white hair, the femora more or less fuscous. The wings reach beyond the apex of the 

 abdomen ; the radial cellule is shorter than the stigma ; the basal abscissa of the radius 

 is oblique, the apical abscissa curved and emitting a short branch ; the second cubital 

 cellule is much narrowed at the top, the first and second transverse cubital nervures 

 converging there ; the first recurrent nervure is received in the basal third of the 

 cellule, the second almost in the middle of the cellule ; the transverse basal nervure is 

 interstitial. 



biol. centb.-amek., Hymenopt., Vol. IL, February 1899. 3 ff 



