202 



KALTICIN^. 



Genus CHiETOCNEMA, Stephens. 



Chcetocnema, Steph., 111. Brit, iv, Ent. 1831, p. 325 ; Chapuis, Gen. 



Col. xi, 1875, p. 49 ; -b owler, Col. Brit. Is. iv, 1890, p. 385. 

 Udorpes, Motsch., Bull. Soc. Nat. Mosc. xviii, 1845, part 1, no. 1 , p. 107. 

 Ydorpes, Motsch., op. cit., addendum at end of volume. 

 Hydropus, Gemminger & Harold, Cat. Col. xii, 187(5, p. 3519. 

 Tlanoma, Motsch., Bull. Soc. Nat. Mosc. xviii, 1845, part 1, no. 1, p. 108. 

 Plectroscelis, liedtenb., Fauna Austriaca, 1st ed., 1849, p. 539, 2nd 



ed., 1858, p. 946 ; Chapuis, Gen. Col. xi, 1875, p. 48 ; Fowler, Col. 



Brit. Is. iv, 1890, p. 388. 



Genotype : Altica hortensis, Geoff roy, in Fourcroy, Ent. Paris, 

 1785, p. 98 = Galeruca aridella, Paykull, Faun. Suee. ii, 1799, 

 p. 111. 



Sometimes Tlanoma, Motsch., is regarded as a subgenus of 

 Chcetocnema ; the type of Tlanoma was fixed by Motschulsky as 

 Haltica dentipes, Koch, Ent. Heft, ii, 1803, p. 38 = Ghrysomela 

 concinna, Marsham, Ent. Brit, i, 1802, p. 196. In proposing the 

 genus Chcetocnema Stephens cites aridella as the first species, and 

 this has been tacitly adopted as the type, although, as far as I am 

 able to find out, it has not before been definitely fixed and published. 



Small oval beetles, narrowed in front and behind, those from 

 within our limits varying in size from one and a half to about 

 three millimetres. Colour dark, often green with bronzy reflec- 

 tions ; almost always the basal five or six segments of the antennae, 

 the front and middle legs and the posterior tibiae and tarsi, are 

 brown. Head, generally broad without any frontal elevations; in 

 one or two cases the interantennal space is very slightly and 

 broadly raised ; very often there is in the interocular space just 

 above the roots of the antennae a transverse impression, which is 

 joined on each side by an impressed oblique line ; this latter usually 

 touches the upper edge of the eye at a tangent ; in some cases a deep 

 and more or less broad pit adjoins the inner margin of the eye; the 

 whole surface may be punctate or im punctate or finely granulose, 

 sometimes there are punctures on a granulose surface ; inter- 

 antennal space not very narrow; labrum often large, covering the 

 mandibles. Antennae never as long as the body, at least in those 

 species from our regions ; their length varies from reaching as far 

 as the humerus to attaining the middle of the elytra; basal segment 

 always thick and club-shaped, second as thick as, but always 

 shorter than, first and always thicker than third ; third to sixth 

 segments generally of more slender build, their relative lengths 

 varying to a certain extent ; seventh to eleventh often somewhat 

 stouter ; the antennae are generally very sparsely scattered over 

 with fine hairs. Eyes generally strongly convex and more or less 

 widely separated. Prothorax always broader than long, front 

 margin more or less nearly straight, basal margin sometimes 

 slightly produced into a lobe in the middle, lateral margins 

 generally somewhat rounded, in some cases straight, each of the 

 anterior and posterior angles bearing a fine seta arising from a 



