244 



IXSECTA. 



sinian grasshopper (Jig. 107, E) the arrangement of these organs is 

 well exhibited. 



(285.) The next modification in the structure of the legs is met 

 with in such species as burrow beneath the surface of the ground, of 

 which mode of progression the most remarkable example is seen in the 

 mole-cricket (Gryllo-talpa vulgaris) (Jig. 108). In this creature 



Fig. 103. 



the anterior segment of the thorax, whereunto the fore-legs are ap- 

 pended, is wonderfully enlarged, and of great strength, while the 

 legs themselves are equally remarkable for their enormous bulk and 

 muscularity. The tibia is excessively dilated, and terminates ob- 

 liquely in four sharp and strong spines. The whole of the tarsus 

 would, at a first glance, appear to be wanting ; but on inspection it 

 is found to consist of three joints placed upon the inner side of the 

 tibia, the two first being broad and tooth-shaped, while the last 

 piece is very small, and armed with two hooks. The direction and 

 motion of these hands is outwards, thus enabling the animal most 

 effectually to remove the earth when it burrows, and by the help of 

 such powerful instruments it is astonishing how rapidly it buries 

 itself* 



(286.) Similar examples of adaptation in the mechanical structure 

 of the legs of insects might be multiplied indefinitely ; we shall, 



* Kirby and Spence. Introd. to Ent. vol. ii. p. 362. 



