COLEOPTERA. 389 



hairs, terminate in a triarliculated club. It forms the genus 

 Trinodes, Megerl., and Dej.(l) 



On similar grounds we might also separate from the Byrrhii 

 some other analogous species(2), in which the antennal club con- 

 sists of but two joints, the last much the thickest and nearly 

 globular. 

 All the Byrrhii remain on the ground in sandy localities(3). 



It is impossible to describe the Clavicornes of our second 

 section, although a very natural one, but by the reunion of 

 several characters. Some of these Insects are removed from 

 all others of the family by their antennae, which consist of nine 

 or six joints ; they are those, which, in this respect, seem to 

 approximate most closely to the Palpicornes. The antennae 

 of the other Clavicornes of the same section are composed 

 of eleven or ten joints ; but sometimes they are not much 

 longer than the head, and from the third joint form an almost 

 cylindrical or fusiform club, arcuated and somewhat serrated; 

 sometimes they are nearly filiform and as long as the head 

 and thorax united; but here, as in most of the other subgenera 

 of the same division, the tarsi are terminated by a large joint 

 furnished with two strong terminal hooks. Those of some 

 Heterocerus, Georissus consist of but four joints. 



The body of these Insects is generally ovoid, and their head 

 plunged to the eyes in a trapezoidal thorax, with a recurved 

 lateral margin, and terminating posteriorly in acute angles; 

 the presternum is dilated anteriorly (4), and the legs are im- 

 perfectly contractile. They are found in the water, under 

 stones in the vicinity of shores, and frequently in the mud : 

 some of them Dryops are allied to the Gyrini by the struc- 

 ture and shortness of their antennae. 



(1) JLnthrenus hirtus, Fab.; Panz., Faun. Insect. Germ., XI, 16. 



(2) Byrrhus erinaceus, Ziegl.; B. setiger, Illig. 



(3) For the other species, see Fabricius, Olivier, Schcenherr, Gyllenhal, &c. 

 The genus Murmidius, Leach, according- to that gentleman, belongs to this 



tribe. The antennae are composed of but ten joints, the last of which forms an 

 ovoido-globular club. See Lin. Trans., XIII, p. 41. 



(4) The Potamophili excepted. 



