360 INSECTS ABKOAP. 



There is another peculiarity which is worthy of remark. The 

 Dragon Flies prefer for their sport sunshiny days with frequent 

 gusts of wind. The warm sunshine attracts into the open air 

 the insects on which Dragon Flies feed, and the gusts of wind 

 render them an easy prey to their pursuer. Many insects are 

 almost helpless in the wind, especially if it should come on by 

 fits and starts, while the firm, strong pinions of the Dragon Fly 

 render it almost independent of wind, and give it a tremendous 

 advantage over its weaker-winged prey. 



We now come to the second group of Dragon Flies, namely, 

 the Agrionidoe. This name is formed from a Greek w r ord sig- 

 nifying something that lives in the open air. 



These insects are very familiar to us on account of the beau- 

 tiful species which are so plentiful about our brooks, ditches, 

 and ponds. The most conspicuous of them is one of the hand- 

 somest of all the Dragon Flies, the male being rich blue, with 

 black wings, and the female all shining green. It is generally 

 known by the popular name of Demoiselle. Unlike the pre- 

 vious group of Dragon Flies, which Hy far and wide in search of 

 prey, most of the Agrionidse of this country confine themselves 

 to the vicinity of the water in which they had passed their 

 larval and pupal stages, so that any entomologist who wishes to 

 capture these pretty insects may feel tolerably sure of success 

 if he hunts along the water-side. 



o 



The lovely insect shown in Fig. 170, which is appropriately 

 called Euphcca splcndens, is a native of India. The generic name 

 Euplicva is composed of two Greek words signifying something 

 that is beautiful in appearance, and the Latin specific name 

 splcnclcns explains itself. 



At first sight, if viewed directly from above, the insect 

 appears to be entirely brown, and requires a rather strong side- 

 light to bring out all its beauties. When so viewed, the upper 

 wings still retain their brown hue, but the lower pair Hash out 

 into vivid metallic green. The brilliancy of this colour is in- 

 creased by the structure of the wing, the surface of which is 

 formed into innumerable parallel ridges that break up the light, 

 and give a singular richness of effect to the green hue. All 

 the wings are transparent and colourless at their bases. 



