394 Mr. F. Smith on a new species of Hymenopterous Insect. 



nirostris, Lesson, and strigatus, Eyton, the adults of which are 

 very dissimilar from those of the two other species. 



In the reprint from Capt. Begbie's work (xvii. 395), the Bu- 

 ceros lugubris of that gentleman is the only species which I shall 

 here refer to, it being the adult male of B. sumatranus, Raffles. 

 There are numerous errors of identification in that paper which 

 I shall have another opportunity of correcting. The reduction 

 of nearly all of Mr. Eyton' s " apparently new species of birds 

 from Malacca n (xvi. 227) has been effected partly by myself in 

 the ' Journ. As. Soc. Bengal/ xv. 10 and 52, and the rest by 

 Mr. Strickland, vide p. 129, &c. ante. 



XL. — Description of a new species of Hymenopterous Insect be- 

 longing to the family Sphegidse. By Frederick Smith. 



[With a Plate.] 



Section ACULEATA. 



Family Sphegid^e. 



Genus Stethorectus, Smith. 



Head large, as wide as the thorax, subquadrate, attenuated pos- 

 teriorly ; eyes large, oval ; the stemmata placed in a triangle at 

 the vertex ; the antennae gradually attenuated, inserted near the 

 base of the clypeus, which is quadridentate in front, the two exterior 

 teeth largest. Mandibles large, stout, arcuate, smooth exte- 

 riorly ; the maxillary palpi six-jointed, the terminal joint very 

 minute ; the labial palpi four-jointed, the terminal joints conical. 

 Thorax elongate, the collar elongate, of a pyramidal form above ; 

 the superior wings with one marginal and three submarginal cells, 

 the first as long as the two following, the second nearly quadrate, 

 slightly narrowed towards the marginal, receiving the first and 

 second recurrent nervures. The posterior legs elongate. Abdo- 

 men ovato-conical, abruptly petiolated. 



Sp. ingens. Female (length 2 inches 2 lines). Black, very smooth 

 and shining. Head slightly attenuated posteriorly, a little black 

 pubescence on the face above the base of the antennae, a smooth 

 depression on each side of the posterior stemmata running a little 

 way backwards, a thin pubescence on the cheeks. Thorax slightly 

 pubescent at the sides, a strongly marked epaulet passing over 

 each tegula and reaching as far as the scutellum, which is very 

 smooth and shining; the wings dark metallic blue; the meta- 

 thorax opake, having above a deep longitudinal channel, which 

 is, as well as on each side of it, transversely wrinkled ; the apex 

 transversely sulcate ; towards the apex, laterally, is a smooth space 



