AND HABITS OF THE YELLOAV DUNG-FLY. 647 



Natimxd Enemies. 



JSTiitural enemies were not observed. Tlie Scarabeid and 

 Stapbylinid beetles and tbeir lai-vfe, wliicb breed in dung, do not 

 appear to attack the larvse of Scatophaga. 



One Ichneumonid parasite was bred out from pup.-e, but, having 

 failed to reach the surface of the soil, was in too bad a state of 

 preservation to be identified. 



A large numljer of birds arc mentioned by Newstead as feeding 

 on (Scarabeid beetles and Muscid lai'vaj breeding in dung, so that 

 the}^ very probably are a considerable check on the spread of 

 Scatojihaga. 



A number of larvfe are pi-obably destroj'ed by natural con- 

 ditions such as the too rapid drying up of the dung or owing to 

 the dung being trodden on and spread about by cattle. 



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