HOUSE FLIES AND BLUEBOTTLES 



205 



are pale at the base. These four characteristics will 

 probably enable the insect to be recognised. At the 

 moment of writing, it is sharing the window-panes 

 with the smaller house fly and a bluebottle. 



The habits of this fly are apparently very varied. Its 

 larvae have been usually said to live on rotten fungi, but 

 no doubt they also eat decaying vegetable matter of 

 other kinds, and, judging by their abundance in stable- 

 yards, apparently they devour manure as well. But 

 that they are not confined to such diet is proved by the 

 following observations of Mr. J. E. Fletcher: writing 

 in October 1883, he says, "For several years I have 



FIG. 66. Wing of Cyrtoneura stabulans. 



grown a patch of shallots, being uniformly successful 

 with them until last year, when they were moderately 

 attacked by Diptera, which, however, I was glad to find, 

 as I was desirous of breeding them. I noticed two 

 species of larvae, one much larger than the other ; and 

 when the images appeared in the autumn and following 

 spring, they proved to be Cyrtoneura stabulans and 

 Phorbia cepetorum, Meade. This year about a peck of 

 shallots were planted, which should have yielded a crop 

 of, say, seven pecks ; instead of which they yielded little 

 more than a quarter of a peck, the rest having been 

 utterly spoiled by larvae of the Dipterous insects named." 



