COLEOPTERA. — ELATERID^. 235 



The third family Elaterid.^ * Leach, corresponding with the 

 genus Elater of Linnaeus, is very nearly allied to the Buprestidae, 

 having the body of a hard consistence [fig- St. 7. Ludius ferrugineus) ; 

 the antenna? short and more or less serrated ; the legs and palpi are 

 short, and the head immersed to the eyes in the thorax ; the body is, 

 however, more elongated and narrower than in that family ; the pos- 

 terior thoracic angles are produced into an acute spine, whereby all 

 lateral movement is pi'evented, and the insects merely enabled to raise 

 and depress the thorax; the tarsi are slender and simple (^fig. 24'. 13.); 

 the labrum transverse (^fig- 24'. 9. labrum of Agriotes lineatus) ; the 

 mandibles notched at the tip (^fig. 24'. 10.) ; the maxillaj bilobed 

 (^fig. 24. 11.) ; the mentum short, transverse {fig^ 24. 12.), and the 

 palpi terminated by a large triangular joint ; the prosternum is pro- 

 duced behind into an acute compressed spine {fig. 24. 8.), which is 

 received at the will of the animal into a groove in the front of the me- 

 sothorax, in front of the base of the middle legs, the latter peculiarity 

 of structure resulting from the curious power which these insects 

 possess, of springing when laid upon their backs. Being unable to re- 

 cover their ordinary position in consequence of the shortness of the 

 legs, Nature has amply supplied the apparent defect by providing 

 them with an instrument which enables them to recover their position 

 with facility. Folding their legs and antennae close to the body (the 

 latter being lodged in grooves on the underside of the prothorax), 

 they lower the head and thorax until they come into contact with the 

 surface upon which they are laid, by which means the prosternal 

 spine is entirely drawn out of its oval groove in the mesosternum, 

 when, by again suddenly throwing the head and thorax forwards, the 



* BiBLIOGR. Refer, to the ELATERIDiE. 



Eschscholtz, in Thon's Ent. Arcliiv. vol. ii. 



Latreille, in Ann. Soc. Ent. France, 1834. 



Stephens's Illustr. Brit. Ent. Mand. vol. iii. and Nomendat., 2d. edition. 



Serville and St. Fargeau, Encyl. Muthodiq. v. 10. 



Gory, in Ann. Soc. Ent. de France. 



Boisduval. Voyage de 1' Astrolabe. 



Hope, in Trans. Ent. Soc. Lond. vol. i. (Macromalocerus. ) 



Gutrin. Magasin d'Entomol. pi. 9. (Lobaederus.) — Ditto, Icon. R. An. 



Illlr/er, in Der Gcsellsch. Naturf. Freund. Berlin, 1807. 



Sat/, in Ann. Lyceum, New York. vol. i. 



Stevens. Mem. Soc. Imp. JNIosc. t. 8. 



And the general works of Fabricius, Driiry, Herb.st, Olivier, &c. 



Ac- -7- . 



