498 



ACTS OF LEAPING : PLEA : CRICKET. 



of their bodies places them in continual danger of oversetting ; 

 they therefore take a zig-zag course. In ascending a hill, 

 however, their progression is greatly favoured by the length 

 of their posterior extremities (fig. 237). The Rabbit, when 



Fig. 237. HARE ASCENDING A HILL. 



moving slowly, advances the fore-feet two or three steps 

 alternately, the posterior limbs remaining inactive ; and the 

 body having been lengthened by these means, the posterior 

 legs are suddenly extended together, and then drawn for- 

 wards : thus the rabbit walks with the fore and leaps with 

 the hind pair of legs. The Frog moves in a very similar 

 manner. 



662. It is among Insects that we find the most extraordi- 

 nary powers of leaping, considered with reference to the size 



of the animals that 

 possess them. Thus 

 the Flea will spring 

 to a height equal to 

 200 times the length 

 of its body. Let us 

 imagine a Kangaroo 

 or a Tiger doing the 

 same ! In many of 



Fig.238.-C R iCK ET . ^ leaping ingectg> 



the hind legs are of great length, as in the Grasshopper 

 and Cricket tribe (fig. 238); and in one curious family, 

 that of the Poduras or spring-tails, the leap is accomplished 

 by the sudden extension of the tail, which is ordinarily bent 

 under the body (fig. 239). A very remarkable kind of leap is 



