100 Mr. H. W.Bates on the Longicorn Coleoptera 



formed that this specimen came from Natal ; and in the above 

 character it agrees with the two specimens received from Mr. 

 Sargeant ; while in all the specimens of P. subrufa which I have 

 seen, the shell is more or less rufous brown, often very pale, and 

 the shields are smooth, with only a few distant concentric narrow 

 lines, or they are all over smooth, as if worn and polished. 



The three Natal specimens agree also in the under side of the 

 margin being black, with triangular white portions on the inner 

 hinder edge of each shield, and the sternum is black or blackish 

 brown. From this distribution of the colours, I believe that 

 the " Pentonyx du Cap," figured by M. Auguste Dumeril in the 

 ' Archives du Museum,' is this species. 



I have no doubt of these being distinct species, not only on 

 account of their colour, but also on account of the difference in 

 the scales on the crown, which is very similar to the difference 

 that separates the Natal from the Madagascar SternothcBrus. 



XI. — Contributions to an Insect Fauna of the Amazon Valley. 

 Coleoptera : Longicornes. By H. W. Bates, Esq. 



[Continued from vol. ix. p. 458.] 



Subtribe AcANTHOciNiTiE. 



Group Lagocheirina. 



Genus Lagocheirus (Dej. Cat.), Thomson. 



Thomson, Classif. des Cerambyc. p. 9. 



Body of large size, broad, oblong, slightly convex. Antennae 

 stout, half as long again as the body, and of nearly equal length 

 in both sexes; the sixth joint in the males having a tubercle 

 beneath its apex, surmounted by a pencil of stiff hairs; the 

 basal joint is as long as the third, gradually thickened from the 

 base, and in both sexes toothed beneath at the apex. Thorax 

 obtusely tuberculated on its disk, and with large conical lateral 

 tubercles. Elytra very broad at the shoulders, gradually and 

 slightly tapering to the apex, which latter is briefly truncated. 

 Thighs abruptly clavate ; basal joint of the tarsi not much longer 

 than the second. 



The females have not elongated ovipositors and sheaths; the 

 terminal abdominal segments, however, are much longer in the 

 females than in the males. In one of the two species which I 

 have examined {L. araneifonnis) both the ventral and dorsal 

 segments have their apical edges excised, whilst in the other (L. 

 fasciculatus) they are entire. The males have their anterior tarsi 

 ciliated. 



