354 THE NATURAL HISTORY 



been strangely misunderstood. Perhaps when we learn 

 that " Dragon-flies," " Scorpion-flies," and " Snake- 

 flies " belong to this group, we may naturally be pre- 

 pared to meet with some of the most formidable of 

 insects ; but our apprehensions will vanish when we 

 become acquainted with their anatomy and history. 

 Dragon-flies are quite harmless except to the smaller 

 insects on which they prey, and although they are 

 popularly known as "Adder-spears" and "Horse- 

 stingers," these names must have been conferred on 

 them on the principle of " lucus a non lucendo," as 

 they possess neither poison-fang nor sting of any kind. 

 They may be seen any fine day in summer insect 

 hawking, for which pursuit their four powerful re- 

 ticulated wings, efficient jaws, and long slender ab- 

 domen, which acts like the tail of a bird in flight, 

 specially fit them. In the bright sunshine they are 

 very brilliant objects while performing their easy and 

 graceful evolutions over or near a pool of water, from 

 which their living insect food is being constantly 

 liberated. Now they are poising themselves in the air 

 for a few seconds, now darting off at any angle with 

 lightning-like speed in pursuit of their quarry, and 

 again gliding and skimming to and fro over the water, 

 with wonderful command of wing, at one moment 

 within a few inches of the surface, and the next soaring 

 far above the overhanging branches of the highest 

 trees. 



In their preparatory stages they are entirely aquatic. 

 We have often seen the female insect in the act of 

 oviposition on the surface of the water, upheld by the 

 vigorous action of her wings alone her abdomen 

 curved downwards and lightly striking the water each 

 time she deposited an egg her body at the same time 

 gently advancing and retiring in concert with the ex- 

 trusion of the eggs. This operation is not a slow one : 

 we have counted, on more than one occasion, upwards 

 of seventy such movements of the body and abdomen, 



