14 INTRODUCTION. 



The position of the wings when at rest is roofwise over the body 

 and they are covered with curious downy hairs, which under the 

 microscope look like small spear heads and from which the tribe 

 derive their name. They are easy flies to imitate, and well worth 

 using when the naturals are about. 



The ChrysopidcB or Lacewings (plate 8, figs. 75, 76, 77) 

 number 15 species — three of them are frequently seen on and about 

 the water, namely : the green one (Hemcrobius alba) ; the blue one 

 (H. nervosus) ; and the yellow one (H. hirtus) ; and all are taken 

 eagerly by the fish. The blue one at times is seen dancing over the 

 water in hundreds and might be mistaken for a small Caddis Fly ; 

 but its clear, rather iridescent wings and different nervuration 

 quickly reveals its identity. The eggs of this fly are laid on bushes, 

 each egg being carried on a hair-like support attached to a leaf of 

 the bush. The larger species in spite of their ample and resplendent 

 wings have a curiously feeble flight when seen on the wing during 

 the day, but in the dusk develop a surprising turn of speed at times. 



The power of insects on the wing depends more on the size of 

 the thorax than either the size, form, or number of their wings , 

 in other words, a monoplane is quite as good as a biplane, provided 

 the monoplane has sufficient engine power behind it. 



Of the Sialida or Alder Flies (plate 8, fig 80), we have only 

 one example — Sialis lutaria — so common everywhere, sitting on 

 fences or flying over the water. The eggs of this fly are laid in 

 patches on the leaves of marginal plants — one patch at times con- 

 taining over 1,000 eggs — and as they hatch, the larvae make their 

 way down into the water, where they grow during their larval period 

 and then burrow at the margin of the water and spend a short 

 pupal period, emerging to enjoy a time of flight and flirtation and 

 basking in the sun. 



II. Hymenoptera (plate 8, figs. 78, 79, 81-86, and plate 9, 

 figs. 96, 97) possess four wings, membraneous without scales, never 

 very large, the hind pair smaller than the front ; nervures 

 irregular in size and form ; mandibles conspicuous. The females 

 are furnished with a saw, sting, or ovipositor at the extreme 



