330 MAXDIBCJLATA. COLEOPTEUA. 



Ev. nigroreneus. Kirby MSS. — N. G. nigroffineus. Steph. Catal. 294. No. 

 3218. — Syiitomium nigroaeneum. Curtis, v. pi. 228. 



Brassy-black, rather obscure, punctured, glabrous : head narrower than the 

 thorax, subglobose, smooth, with two or three very distinct punctures in 

 front : thorax rather longer than the head, somewhat roughly-punctured, 

 with a slightly elevated ridge in the middle behhid : elytra rather longer 

 and much wider than the thorax, roughly-punctured : abdomen as wide as 

 the elytra, very glossy and minutely punctured : legs and antennae dusky 

 chestnut. 



Mr. Kirby first captured this insect as mentioned below, and in the 

 same locality I took a dozen specimens in Sept. 1821, and afterwards 

 (on Jan. 1, 1825) beneath moss at Ripley; it has been found near 

 Southgate, by Mr. Walker. " Taken beneath grass in Sept. 1802, 

 and again in a chalk pit near Great Blakenham, Suffolk, in July 180G." 

 —Kirbi/ MSS. " Norfolk."—//. Denny, Esq. " Marton Lodge, 

 Yorkshire."— i?e?^ G. T. Rudd. 



Genus DXL. — Megarthrus, Kirby. 



Antenna; subclavate, with the two basal joints very thick, somewhat obconic, 

 the six following small turbinate-globose, gradually increasing in size, the 

 two next larger, transverse, the apical one largest suborbicular. Palpi 

 maxillary (a) with the penultimate joint incrassated, clavate, terminal one 

 more slender, acute: labrum (Z») very narrow, obscurely notched: man- 

 dibles (c) acute, entire: labium {d) bilobed : head subtriangular : ej/e* lateral, 

 rounded, slightly promuient: thorax convex, transverse; a little emarginate 

 in front, straight behind, the sides rounded : body ovate, very slightly con- 

 vex: e/y^ra covering one-third of the abdomen, which is somewhat trian- 

 gular, with its apex slightly acute: legs short ; femora slender, or com- 

 pressed, anterior and intermediate simple, posterior mucronated at the base; 

 tibi(E slightly curved, thickened towards the apex, which in the posterior (e) 

 is recurved, and the inner edge dilated ; intermediate trochanters (/) denti- 

 culate beneath : tarsi pentamerous. 



The two incrassated basal joints of the antennae of the insects of 

 this genus, exclusively of the diversity of structure in the trophi, &c., 

 the broad, depressed, retuse form, elongate elytra, &c., sufficiently 

 point out their distinction from the other genera of this family : they 

 generally inhabit fungi, boleti, &c., the roots of grass, and similar 

 situations during the spring and svimmer months ; though like others 

 of the Brachelytra they may be occasionally found at all seasons. 



