218 MINUTE MARVELS OF NATURE 



evenings for a fortnight or three weeks. Fig. 143 

 shows a May-fly, natural size. 



In the intervals of watching the easy and graceful 

 flight of the May-flies we may have observed, rest- 



Fig. 143. A May-fly. Natural size 



ing on palings or stones near at hand, a number of 

 black-bodied flies, with thick and conspicuous dark- 

 coloured veinings on their smoky wings. These 

 common insects are known to anglers as alder-flies. 

 Fig. 1 44 has been prepared to show their anatomy. 

 This is another of the insects which are always 

 associated with water ; the female deposits an enor- 

 mous number of eggs in patches on rushes or other 

 aquatic plants. A number of these are shown 

 in Fig. 145, being dingy brown in colour and 



