THREE UNDESCRIBED FOSSORIAL HYMENOPTERA. 243 



Clypeus densely covered with silvery pubescence, its centre keeled, 

 the apex of the keel projecting into a blunt tooth. Front minutely 

 punctured, the vertex almost smooth ; the ocelli in a triangle, the 

 hinder separated from each other by about the same distance as they 

 are from the eyes. Mesothorax very minutely punctured. Base of 

 metanotum irregularly striated, its centre furrowed. First abdominal 

 segment longer than the second, longish, its base not half the width 

 of the apex. 



Crabro dentipleuris, sp. nov. 



Black ; antennal scape, a line on apex of pronotum, tubercles, 

 and scutellum yellow, the fore tibiae and tarsi testaceous, the base of 

 the hind tibiae narrowly, and the calcaria and the hind metatarsus to 

 near the apex pale yellow. Wings hyaline, the nervures black. The 

 centre of the lower edge of the propleurae with a stout triangular 

 tooth, behind which is a rounded tubercle. ? . Length, 5 mm. 



Kuching (John Hewitt). 



Eyes distinctly converging below. Apex of clypeus broadly 

 rounded, its centre keeled. Apical half of mandibles rufous. Front 

 closely, distinctly punctured, the vertex almost smooth. Ocelli in a 

 triangle, the hinder separated from each other by about the same 

 distance as they are from the eyes. Mesonotum and scutellum 

 closely, minutely punctured. The whole metathorax smooth and 

 shining, the base with a short distinct furrow ; the apical slope with 

 a wide depression. Propleurae almost smooth, the mesopleuras closely 

 punctured. First abdominal segment clearly longer than it is wide at 

 the apex, the base not quite half the width of the apex. Palpi fuscous. 

 The body is covered with a short silvery pubescence. 



Should be known by the stout, triangular, pleural tooth, 



Psen marginicollis, sp. nov. 

 Black ; the antennal scape, the four anterior tibiae and tarsi, and 

 the tubercles dark testaceous ; the wings hyaline, the stigma and 

 nervures black. Head smooth and shining, the eye orbits with a 

 crenulated border, bounded on the outer side by a distinct keel. Front 

 furrowed down the centre. Ocelli in a triangle, placed behind the 

 eyes, the hinder separated from each other by a less distance than 

 they are from the eyes. Temples broad. Occiput transverse, dis- 

 tinctly margined. Apical half of pronotum raised, the base of the 

 raised part margined, projecting laterally into teeth. Mesonotum 

 almost smooth, its apex with a distinct crenulated furrow, behind the 

 centre of which is a triangular depression. The entire metathorax is 

 coarsely reticulated. Pro- and mesopleurae opaque. The narrowed 

 basal part of the first abdominal segment is opaque, curved, fully 

 one-half longer than the dilated apex. The central part of the pro- 

 pleurae is raised, and it is surrounded above, below and at the apex by 

 a striated furrow ; the central part of the mesopleuras is also sur- 

 rounded by a striated furrow, the lower and upper of which unite 

 at the apex. Length, 4 mm. $ . 



Kuching (Hewitt). 



