148 



NATURAL HISTORY OF ARTHROPODS. 



thus the muscles of flight, which are attached to the side-pieces, have a great develop- 

 ment ; so much so as to give a unique appearance to these creatures. 



Moreover the head of dragon-flies is remarkable for the enormous size of the eyes, 

 which in many of them not only completely encircle, but form a large proportion 

 of the head, so that the head appears " all eyes." The mouth-parts, jaws, etc., are 

 constructed much like those of grasshoppers, but the under lip differs in its strangely 

 modified palpi or feelers, which are broad and saucer-like so as to cover the lower part 

 of the face. Add to these characteristics the long slender abdomen, which balances 

 the body during its rapid, headlong flight, and we have an insect with a decided outre 

 appearance. None of its contours can be said to be lines of beauty, and the dragon-fly 

 is upon the whole one of the most repulsive of insects, though gaily colored, and 

 decorated with the brightest of trappings and spots. In the popular estimation dragon- 



in lie 



a vn vi v 

 213. 



I c 



212. 



vi vir 



II IV VI 

 III V VII 



e I n HI iv n a 

 214. 



215. 



FIGS. 212-215. Development of a dragon-fly; I, antennae. II, mandibles. Ill, maxillae. IV, labium. 

 V-VII, legs, a, abdomen, c, clypeus. e, eye. i, intestine, n, nerve, t, trachea. 



flies hold an unenviable position ; but worse qualities are ascribed to them than they 

 really possess. They do a, great deal of good in devouring mosquitoes, and other 

 noxious flies and insects, as they are continually hawking about after gnats, etc. 



The transformations of the dragon-flies have always attracted interest. They are 

 ' incomplete,' i. e., the larva and pupae are active, creeping about over the bottom of 

 pools among aquatic plants, and feeding upon other aquatic larvae. 



We will now consider the singular mode of egg-laying practised by these insects, 

 and we will tirst quote Mr. Uhler's account. In laying her eggs the Libellula "alights 

 upon water-plants and, pushing the end of her ovipositor below the surface of the 

 water, glues a bunch of eggs to the submerged stem or leaf. Libellula auripennis 

 I have often seen laying eggs, and I think I was not deceived in my observation that 

 she dropped a bunch of eggs into the open ditch while balancing herself just a little 

 way above the surface of the water. I have also seen her settled upon the reeds in 



