80 EVENINGS AT THE MICEOSCOPE. 



fly, witli its four ample and wide-spread wings of 

 gauze, hawking in a green lane, or over a pool in tlie 

 noon of summer. It sails, or rather shoots with arrowy 

 fleetness hither and thither, now forwards, now back- 

 wards, now to the right, now to the left, without turn- 

 ing its body, but simply by the action of its powerful 

 and elegant wings. Leeuwenhoek once saw an insect 

 of this tribe chased by a swallow in a menagerie a hun- 

 dred feet long. The Dragon-fly shot along with such 

 astonishing power of wing, to the right, to the left, and 

 in all directions, that this bird of rapid flight and ready 

 evolution was unable to overtake and capture it, the 

 insect eluding every attempt, and being in general 

 fully six feet in advance of the bird. A Dragon-fly 

 has been known to fly on board a ship at sea, the 

 nearest land being the coast of Africa, five hundred 

 miles distant, a fact highly illustrative of its power of 

 wing. 



It is a point of interest to know the structure of the 

 organs by which such results are accomplished, and 

 therefore we will devote an hour to the microscopical 

 examination of the wings of one or two Insects. Let 

 us begin with the common Fly, one of which, a fine 

 blue-bottle, is somewhat noisily buzzing in the win- 

 dow — 



" The blue-fly sung i' the pane," — 



as if to invite our attention to him. "Well, we will bor- 

 row one of his wings for the lesson : and putting it into 

 the stage-forceps, we shall be able to turn it in any di- 

 rection for observation beneath the microscope. 



At first it seems a very thin transparent membrane, 

 of a shape between triangular and oval, with a few fine 



