COLEOPTERA. 333 



But a small number of species are known, which are not yet 

 described. From Guiana and Brazil. 



Zyrophorus, Dalm. Leptochirns, Germ. Iren&us, Leach. Oxyte- 



lus, Oliv. Piestus, Grav. 



The body depressed; anterior legs only, wider than the rest, den- 

 tated exteriorly; head transverse; thorax square; antennae equal 

 throughout, at least as long as the head and thorax, and composed 

 mostly of oval or cylindrical joints rounded at both ends; mandibles 

 as long as the head, and dentated at the extremity(l_). 



Prognatha, Lat. Blond. Siagonum, Kirby. 



The Prognathse scarcely differ from the Zyrophori except in their 

 filiform antennae, composed of elongated joints(2). 



Coprophilus, Lat. Omalium, Grav. Oliv. Gyll. 



The body still flattened, but all the tibiae dentated or spinous ex- 

 teriorly; antennae much longer than the head, granose, insensibly 

 enlarging towards the end; mandibles almost lunate, arcuated exte- 

 riorly, not sensibly dentated, and their extremity but slightly pro- 

 longed^). 



In the fourth section, that of the Depressa, we find a free head, 

 an entire labrum, and short maxillary palpi of four distinct joints; 

 but the tibiae are simple, or without teeth or spines exteriorly, and 

 the tarsi evidently consist of five joints. 



Here the palpi are filiform. 



Omalium, Grav. 



The thorax as wide as the elytra, wider than the head, and almost 

 forming a transverse square; the angles, or at least those before, 

 rounded, and frequently with a raised lateral margin; the antennae 

 enlarging towards their extremity(4). 



Lesteva, Lat. Anthophagus, Grav. 

 Thorax cordiform, narrowed, and truncated posteriorly, almost 



(1) See Dalman, Anal. Entom. p. 23; his Z.fronticornis, IV, f. 1, appears to be 

 the Oxytelus bicornis, Oliv., Encyc Method. The one he calls penicillatus, lb. f. 2, 

 appears to be closely allied to the Piestus sukatus, Gravenhorst. The Leptochirus, 

 scoriaceus, Germ., Insect. Spec. Nov. I, 1, is a very distinct species. 



(2) Siagonum quadricnrne. Kirby and Spence, Introd. to Entom., I, 1, 5; Blon- 

 del, Ann. des Sc. Nat. Avril 1817, XVII, 1417. 



(3) Omalium rugosum, Gravenhorst, and other species with short elytra. 



(4) See Gravenhorst, Encyc. Method., art. Omalic, and Gyll., lb., p. 198. 



