366 Mr. E. E. Turner on Fossorial Hymenoptera. 



IJab. Shillong, Assam, 5000 feet (G. Turner) ; May, 5 ? , 



2 c?. 



The male differs from the European D. corniculus, Spin., 

 in having the posterior ocelli nearer together and the front 

 more coarsely sculptured, also in the convergence of the 

 carinte of the median segment. The female is without the 

 lateral spines of the median segment, and has the posterior 

 ocelli nearer together and the front more coarsely sculptured 

 than in the same sex of corniculus. The shape of the cubital 

 cells does not seem to be quite constant, and cannot be 

 relied upon for small specific distinctions. It is just possible 

 that this species may be identical with the S.-European 

 D. h(e7norrhous, Costa, which I have not seen. But Schulz 

 (Zool. Annal. iv. p. 147, 1911) treats that form as a mere 

 colour-variety of corniculus. From the similarly coloured 

 D. Ignitus, Sm. (syn. D. tertius, Sauss.), from S. Africa, 

 this species differs in the sculpture of the front and median 

 segment, in the lesser distance between the posterior ocelli, 

 and the greater distance between the eyes on the vertex. 



The female is the type. 



Genus Trirhogma, VVestvv. 



Trirhogma carulea, Westw. 



Trirhogma ccerulea, "W estw. Trans. Ent. Soc. Lond. iii. p. 225 (1842). J ; 

 Westw. Arc. Ent. ii. p. 67 (1844). c? 2 ■ 



It is remarkable that all males which I have seen from 

 India are of the form prismatica, Sm., which has a large 

 tubercle on the scutellum and the base of the mandibles 

 white ; Westwood^s description does not make any reference 

 to these points, though taken from a North-Indian 

 specimen. All females from India seem to be without the 

 tubercle. Males in the British Museum collection from 

 Celebes answer well to Westwood's description, and Colonel 

 Bingham's account of cm'ulea ^ (Faun. Brit. Ind., Hym. i. 

 p. 262) seems to be taken from these rather than from 

 Indian specimens. I have not seen the types, but if the 

 type c? is similar to the Celebes form, I do not consider 

 that it can be the $ of the usual Indian form, for which 

 the name prismatica, Sm., would liave to stand. A male 

 from Hongkong in the British Museum collection has the 

 tubercle on the scutellum less strongly developed than Indian 

 specimens. I consider that only one species of the genus 

 occurs in India. 



