SHEEP MAGGOT FLY LUC I LI A CAESAR L. 205 



such substances the larva'e are able to feed. In Europe the hirvae 

 feed on the matted wool and on the flesh of the backs of sheep, 

 from which habit they are popularly known as " sheep maggots." 

 In Canada, however, as a result of a careful inquiry I have only 

 been able to discover a few cases of such a feeding habit for the 

 larvae, which results in the production of large ulcerated areas on 

 the backs of the sheep, causing severe loss of flesh and sometimes 

 death. Banks (1912) states that Meinert has reared Lucilia 

 nohilis from larvae taken from the ears of a sailor. An excellent 

 account of the Lucilia flies has been given by MacDougall (1909), 

 and Herms (1911) gives a full account of the habits of L. caesar. 

 In England I have usually obtained it from the backs of sheep. 

 Howard (1900) reared it from human excrement. 



The larvae are very similar to those of C. erythrocephala except 

 in size, and Portchinsky considered them otherwise indistinguish- 

 able. The full-gi'own larva measures 10 to 11 mm. in length. 

 The larval life lasts about fourteen days and the pupal stage a 

 similar length of time, but my experience in the field would lead 

 me to believe that under favourable conditions development may 

 be completed in a much shorter time. 



Protoca lliphora groenlandiga . 



In the careful investigation which he carried out Hamer (1908 

 and 1910) found this species, and occasionally P. azurea, in the 

 neighbourhood of a glue and size factory, and also at a railway siding 

 to which were brought, in addition to stable manure and other 

 refuse, the bones for the glue factory. Hamer states that so 

 numerous were the larvae in the sacks of bones that " the ground 

 beneath some vans containing these sacks was found one day last 

 summer to be covered with larvae so that from a little distance 

 this portion of the yard surface had the appearance of snow." The 

 adult flies were caught in the neighbourhood of the factory from 

 the middle of June until mid-September and it was found that 

 the adoption in the late summer of a system of destroying the 

 larvae had some influence in lessening the fly nuisance in sur- 

 rounding houses. 



The larvae of Protocalliphora are similar to those of CaUiphora. 



