Genera of the Cossonidce. 555 



is not lengthened) being especially more incrassate, and 

 its club comparatively small and narrow; in its meta- 

 sternum being a trifle more elongate ; and in its coxae 

 being a little less widely separated. 



64. RHOPALOMESITES (nov. gen.'}. The type of this 

 genus I regard to be the M. Tardii, of western Europe, 

 an insect which ranges likewise to the Azores; and 

 associated with it are several species from the Madeiran 

 and Canarian archipelagos, two of which (namely the 

 maderensis, and the Teneriffan and Gomeran persimilis), 

 although with small distinctive features of their own, may 

 possibly prove to be, in reality, but geographical modifi- 

 cations of the Tardii. The members of this group differ 

 from Mesites proper, chiefly, in their male rostrum being 

 considerably longer and slenderer, and proportionately a 

 little more widened at the point where the antennae are 

 inserted ; in the latter (which are implanted either in or 

 before the middle, in that particular sex, instead of 

 behind it) being very much thinner and more elongate, 

 with the scape especially, and second funiculus-joint, more 

 lengthened, and with the club very much larger and more 

 abrupt; in their head being less incrassated and their 

 eyes more approximate; in their legs being relatively a 

 little longer, and rather more widely separated at the base ; 

 and in the third articulation of their feet being appreciably, 

 though minutely, bilobed. They are also a trifle less 

 cylindrical than the true Mesites (having a more evident 

 tendency to be subfusiform), as also a little less convex, 

 and not quite so shining ; their prothorax is more trian- 

 gular (or less oblong\ and is more conspicuously channelled 

 behind in the males and carinated in the females ; and 

 they are often sparingly clothed with an exceedingly 

 delicate sericeous pubescence. 



65. ODONTOMESITES (nov. gen.). Two of the (so-called) 

 Mesites from the Canarian archipelago, and one from the 

 Cape Verdes, I had long ago detached from the re- 

 mainder, making them to constitute a distinct section of 

 the genus, in which the body is more fusiform and de- 

 pressed, and the male femora are furnished beneath with 

 an obtuse anguliform tooth ; and it is quite clear, there- 

 fore, that if the Tardii and its immediate associates be 



TRANS. ENT. SOC. 1873. PART IV. (OCT.) R R 



