112 Cameron, Hymcnoptera Orientalia. 



all of them by the median segment having only one 

 transverse keel, and consequently no areaae; by the meta- 

 tarsus being longer than all the other joints united; and by 

 the more slender j^etiole. As, owing to the similarity of 

 the alar neuration, these little-known genera are apt to be 

 confounded, it may be advisable to give a synoptical table 

 of their differences. 



A. Middle lobe of the mesonotum triangular, tiansverse 



at the base ; the legs short, stout, the fore claws 

 bifid. 



Colour Ijlack ; the median segment areolated all over, 

 the spiracles placed behind the middle of the 

 petiole. Macrogaster. 



Colour luteous, the median segment not areolated all 

 over: the spiracles placed in the middle of the 

 petiole. Chreusa. 



B. Middle lobe of the mesonotum not triangular, rounded 



at the base ; the legs long and slender: the fore 

 claws simple. 

 Median segment areolated, the post-petiole distinctly 

 dilated ; the metatarsus not longer than the other 

 joints united. Hcmigaster. 



Median segment not areolated, the post-petiole not 

 dilated ; the metatarsus longer than all the other 

 joints united. Arthula, 



Artiiula BRUNNEOCORNIS, sp. nov. 



Nigra; capitc thoraccque flavo-viacidatis, pcdibus iiigris, 

 jlavo-Diaculatis ; abdoviine fcrriigineo ; alls Jiyalinis, stig- 

 niatc fusco. ? . 



Long. II — 12 mm. 



Antennae as long as the abdomen, stout, scarcely 

 tapering towards the apex, dark brownish, darker above ; 

 the scape bright lemon-}'ellow. Head black ; the face, 

 clypeus, labrum, and the orbits all round, lemon-yellow ; 

 the base of the clypeus, an oblique mark on either side of 



