Orchettina.~\ RHTNCHOPHORA. 255 



Two genera are represented in Europe, both of which are found in 

 Britain : they may be distinguished as follows : 



I. Antennae geniculate, inserted at the sides of the rostrum, 



before the eyes OBCRKSTES, III. 



II. Antennae straight, inserted at the base of the rostrum, 



between the eyes RHAMPHUS, Cfain'. 



ORCHESTES, Illiger (Rhynchcentis, Clairville). 



This genus contains about fifty species, of which more than thirty are 

 found in Europe ; the remainder occur in Northern and Southern Africa, 

 the Caucasus district, North America, &c. ; the precise number of British 

 species is not quite certain as two or three have their claim to be indi- 

 genous based on single specimens, and require further confirmation ; if, 

 however, we include 0. sjjarsus, O. decoratus and O lonicene the num- 

 ber of species hitherto found in this country is fifteen, which is a very 

 good proportion ; as a rule they may be known by the thickened 

 posterior femora, but this is hardly noticeable in the very small species 

 O. saliceti ; the antenna? are geniculate and inserted at the sides of the 

 rostrum before the eyes, and the anterior coxae are contiguous; the head 

 is small and the upper surface is almost entirely occupied by the eyes 

 which nearly meet, in many cases, on the vertex ; the thorax is very 

 small in proportion to the elytra and only about half as broad as the 

 latter ; the scutellum is distinct ; the elytra are large in proportion to 

 the rest of the body and are often very prettily variegated ; the femora, 

 besides being almost invariably thickened, are longer than the tibia; in 

 the males the rostrum is duller and proportionately smaller than in the 

 females, but this is not very marked except in O. lonicerte, and there 

 are also slight differences in the insertion of the antennae and the shape 

 of the pygidium and the apex of the last ventral segment of the abdo- 

 men, which, however, do not call for any particular notice ; they are all 

 small or very small insects, ranging from 2 to 3i mm. in length. 



The larvae of several species have been observed and noted by various 

 writers ; that of 0. fagi will be found figured by Westwocd (Classifica- 

 tion I. p. 336, fig. 41, 19) ; it is rather peculiarly formed, being dilated 

 towards the front and tapering towards apex, but possesses no legs ; 

 according to Bouche the larva of O. scuteUaris, which mines the leaves 

 of birch in May, is furnished, at the extremity of its pointed terminal 

 segment, with a brown point, as well as with six short legs, but there is 

 probably some mistake, as these characters have not been observed in 

 any other allied larvae; the habits of A. alni are well known; 

 they mine the parenchyma of leaves of the elm and towards the 

 end of autumn these may be seen, in certain localities, covered with 

 more or less small raised yellowish or brownish knobs ; the larvae will be 

 found in these, and when full grown they construct a small cocoon inside 



