120 AMERICAN COLEOPTERA. 



and the semi-transparent membranous border, which is here tolera- 

 bly persistent, is only rarely represented in a modified form in 

 Lathridius. To this we may add that the first two tarsal joints are 

 nearly equal in Goninomus, and the antennae are much shorter. 



Those characters upon which so much reliance was formally 

 placed, viz.: — the 2-jointed antennal club and longer tempora, are 

 now seen to be of no value; in fact, as the somewhat numerous 

 exotic species of Coninomus have become known, it is found that 

 the greater number have a 3-jointed club, while in Lathridius arma- 

 tulus the tempora are distinctly longer than in Coninomus australicus. 



From Eniemus, Coninomus is always separable by the diseal 

 costee of the pronotum, as well as by the incised margin and mem- 

 branous border. 



Our three species separate very simply. 



Elytra uot tuberculate. 



Antennal club 2-jointed, tempora subequal in length to the eyes. 



const ri etas. 



Antennal club 3-jointed, tempora about half the length of the eyes. 



australicus. 

 Elytra tuberculate iiodifer. 



Strangulatus Mann, is unknown, and the description is too short 

 to do more than indicate its generic position. It is, without much 

 doubt, only another synonym of const rictus, and if so, is the fifth 

 one made by the same author. 



<J. COiistrictus Gyll. — Moderately elongate, feebly convex, glabrous, color 

 varying from testaceous to piceous, the legs and antennae paler in the darker 

 specimens. Head rather longer than wide, rugosely punctate ; front canalicu- 

 late, the channel broader behind ; eyes prominent, tempora subequal in length 

 to the eyes, and usually distinctly though slightly convergent. Antennae short 

 and compact, scarcely reaching the middle of the prothorax; club 2-jointed; 

 joints 7-9 about as wide as long. Prothorax nearly as wide as long, sides a little 

 rounded and subparallel to behind the middle, where they are deeply incised ; 

 margined from apex to base with a semi-transparent whitish membrane, which 

 is quite persistent but seldom perfect, except in fresh specimens; disk punctate 

 and longitudinally biearinate, the posterior transverse impression moderately 

 deep; there is usually plainly visible a short carina on each side at about the 

 middle, nearly parallel with the diseal costse, and about midway between them 

 and the side margin. Elytra elongate-oval, about twice as wide as the prothorax, 

 moderately coarsely punctate-striate ; intervals 3-5 ? distinctly but not strongly 

 costiform. Metasternnm with a few punctures anteriorly, and with distinct 

 post-c.oxal fovea 1 , from which radiate rather short elevated rug;e. Abdomen im- 

 punctate. (PI. Ill, fig. 15). Length 1.25-1.75 mm. 



Hub. — This cosmopolitan species is rather common and widely 



