252 



ANNUL AT A. 



The gnats have aquatic larvae, the eggs being laid on the 

 surface of the water. The Hessian Fly and the Wheat 

 Midge both belong to the same genus, and both are 

 destructive to crops, the larvae feeding on the leaves or 

 flowers. The common "daddy-long-legs" or crane-fly has 



Fig. 172.— The Daddy-Long-legs or Crane-Fly {Tipula oleracea). 



Male and also larva on the left, the female and the pupa on the right. 



a larva which feeds underground on the roots of grass. 

 The bot-flies have a peculiar life-history. The common 

 " horse-bot " lays its small white eggs on the hair of the 

 horse. The larva is found in the stomach of the horse 

 and may give rise to serious inflammation. Other *'bots" 

 live in the nasal cavity of the sheep or under the skin of 



The Horse-Bot {Gastrus equi). 



^-r- 



A C B E D 



A, Egg on a horse-hair ; C and B, larvae ; D, pupa case ; and E, the fly. 



