ELATERIDAE. ' 183 



Tarsi simple. 



Lateral marginal line befon.-ing inferior 



Body winged, elytra free. Cardiophorus. 



Body apterous, elytra connate. Coptostethus 



Lat(!ral marginal line strictly lateral. Hoiistonotus 



Tarsi with fourth joint lobed beneath. Esthesopus. 



Group II. — Cryptohypni. 



This group contains only small species, and is easily known 

 by the margined front, the suddenly dilated coxal plates, and the 

 broad prosternum, with tlic sutures single, and convex outwards; 

 the coxal plates are scarcely toothed at the insertion of the 

 thighs; the tarsi are filiform. 



Cryptohypnus is generally diffused; ffidostethus contains but 

 one species from the Atlantic district. 



Claws simple* tarsi moderate, clothed with stiff hairs. Cryptohypnus. 

 Claws with a tooth at the middle ; tarsi long, pubescent. CUdostethus. 



Group III. — Physorhini. 



The small number of species constituting this group have the 

 third joint of the tarsi furnished beneath with a membranous 

 lobe, the fourth being small, and received upon the third. The 

 front is very convex, its anterior margin rounded; the posterior 

 coxal plates very narrow externally, suddenly dilated and strongly 

 toothed internally; the claws are simple; the mesosternum always 

 oblique; the prdsternal sutures double, and excavated in front. 



The genera of this group are not well defined, the characters 

 separating them being derived from the form and size of the 

 second and third joints of the autonnoe. Anchastus alone occurs 

 in our fauna; two genera have been separated from it, based on 

 characters which have become evanescent by the discovery of 

 other species. 



Group IV.--Monocrepidii. 



In this group the front is convex, margined in front; the first 

 joint of the antennae is longer than usual; the prosternal sutures 

 are double, straight or concave, and scarcely excavated in front; 

 the coxal plates are suddenly dilated internally, with the angle 

 rounded, as in Drasterius, and a tooth at the origin of the thighs, 

 the fourth joint of the tarsi is obliquely prolonged into a mem- 

 branous lobe. 



