HYMENOPTERA OF SARAWAK. 163 



Front and vertex closely, strongly and uniformly punc- 

 tured, the clypeus more sparsely punctured and covered with 

 white pubescence ; it is slightly longer than its greatest width ; 

 the apex has a shallow, wide rounded incision. Apical two 

 joints of antennae brownish beneath, the claw is not quite so 

 long as the joint. Thorax closely rugosely punctured; the apex 

 of the median segment is less strongly punctured ; its sides are 

 straight and obliquely narrowed towards the centre, which is 

 furrowed ; the slope is almost vertical. Abdomen punctured 

 like the thorax ; the basal segment with a stout keel near the 

 base. 



Belongs to the group of 0. sicheli. It is not unlike 0. ro- 

 bertianus, but that species has the clypeus longer compared 

 with its width, broadly marked with black in the middle, depressed 

 at the apex, which is not so broadly rounded and depressed 

 down the middle, the scutellums have a more distinct oblique 

 slope from the base to the apex, the scutellum in matcmgensis 

 being much more convex and without a distinct slope. 



Dielis truscanensis, sp. nov. 



Black, the sides of the clypeus broadly — the yellow line 

 becoming slightly broader towards the apex, — the upper part 

 of the mandibles, a line on the pronotum, broadest in the middle, 

 bands on the apices of the basal 4 abdominal segments, com- 

 mencing from shortly behind the middle and the outer side of the 

 tibiae, yellow. Wings clear hyaline, iridescent, the nervures 

 and stigma black. Head, thorax, base of abdomen and its ven- 

 tral surface thickly covered with long white hair ; the basal 4 

 segments fringed with similar ; the apical thickly with black, 

 stiffer hair. Ocellar depression with curved » trise on the sides. 

 Mesonotum and sides of scutellums punctured, but not closely 

 or strongly ; the metanotum at the base sparsely haired and punc- 

 tured the rest thickly covered with longish white hair. $ • 



Length 13-14 mm. 



Hab. Trusean. 



The black basal bands on the 2nd to 4th abdominal seg- 

 ments are slightly dilated in the middle ; the wings are slightly 



R. A. Soc, No. 44, 1905. 



