556 Mr. T. Vernon Wollaston on the 



disunited from Mesites proper (as I cannot but think is 

 absolutely necessary), these three species must likewise 

 form a separate, though closely allied, group. In their 

 smaller size, more fusiform outline, and general structure, 

 they are of course nearer to Rhopalomesites than to Mesites ; 

 nevertheless they have a more decided tendency to posterior- 

 attenuation than even the smaller members of the former, 

 and (in addition to the subdentate femora to which I have 

 just alluded) they possess a very peculiar feature in the 

 fact of their male rostrum being fringed with elongate 

 fulvescent hairs, on either side, from the point at which 

 the antennas are inserted to the apex. Added to which, 

 their rostrum in the opposite sex is less abruptly thickened 

 at its extreme base ; their legs are proportionately a trifle 

 more incrassated, and the intermediate coxae wider apart ; 

 and the third joint of their feet is, as in Mesites proper, 

 quite unexpanded and simple. 



The species of Odontomesites, so far as I have hitherto 

 observed, are attached exclusively to the rotten stems and 

 branches of the various Euphorbias. 



[66. PORTHETES (Schonherr, Gen. et Spec. Cure. iv. 

 1041. 1838). The genus Porthetes was founded to receive 

 a Cossonid (the P. zamia, Bohem.) from southern Africa ; 

 and although I have not been able to procure an example 

 for inspection, the published diagnosis appears to be suffi- 

 cient to render its peculiarities intelligible. It is described 

 as having much the primd facie aspect of Mesites., the 

 type being a little shorter, but a trifle wider, than the 

 European Cossonus ferrugineus, and of a blackish hue, 

 with the elytra ferruginous. As in Mesites and its imme- 

 diate allies, the rostrum (and to a certain extent, even the 

 antennae) vary according to the sex, it being in the males 

 thickened throughout its basal half, with the anterior por- 

 tion narrow and cylindrical (the exact reverse, be it ob- 

 served, of what is the case in the forms around Mesites), 

 but in the females incrassated (as in those groups) at the 

 'extreme base only. Its antennae (which are abbreviated) 

 are shorter in the females than in the males, and are 

 Z>as//y-inserted in the former sex but medially in the 

 latter ; and the scape is more powerfully clavate in the 

 males than in the females. In its third tarsal joint, too, 

 being somewhat expanded and bilobed Porthetes recedes 

 from Mesites and Odontomesites, and is more on the 

 Rhopalomesites pattern.] 



