A F^ROZEx World 



22 i 



This rapid skiimnin^ in curves or circles on tlie 

 surface of the water is produced in a most interest- 

 inj^ way hy the co-operation of the various pairs 

 of legs, whicli 1 can best explain by the analogy of 

 the bicycle. The two sh( rter and active hind-legs 

 produce the quick forward dart, just as the main 



NO. 7.— IHK WHIKI.UJK; HEJill.K IN SUMMER, DANCING. 



motion of the cycle is given it by the back wheel ; 

 the lousier front le<is act like the front wheel of the 

 cycle in altering the direction ; one of them is 

 jerked out to right or left, rudderwise, and gives 

 the desired amount of curve to the resulting motion 

 according to the will and necessities of the insect. 



