Sl'EGfES'OF CESTRUS. 355 



manifestly to depend almost entirely on the habitat, 

 tloes not appear to have been observed by any suc- 

 ceeding writer since it was mentioned by its discover- 

 er. Humboldt, however, when occupied with his 

 highly interesting travels in South America, was 

 struck with certain tumours that he sometimes ob- 

 served to exist on the bodies of the natives of that coun- 

 try? and which he attributed to the concealed opera- 

 tion of the larva of an oestrus ; but as he had no oppor- 

 tunity of verifying this conjecture by satisfactory ex- 

 amination, he relied upon the form and appearance 

 of the tumours, with a recollection, probably, of the 

 description above quoted. 



Clarke, the best writer on this genus of insects, ob- 

 serves that the hominis is probably a spurious spe- 

 cies, and he further states that it " is, perhaps, mere- 

 ly an accidental deposit of ce. bovis, in the human 

 body, of which there are numerous instances."* 



So perfectly satisfied was Fabricius of the non-ex- 

 istence of the hominis as a distinct species, that in his 

 Systema Antliatorum he has taken no notice what- 

 ever of this name and description. 



The most eminent of living entomologists, Mr. Lat- 

 teille, observes! thai neither of the authors who have 

 mentioned this insect, saw it in its perfect state ; he 

 therefore thinks it probable, that the larvae to which 

 they had reference, were those of the Musca car- 



* Rees' Cyclopaedia, article Bots. 



t Nouveau, did. d'Hist. Nat. article CEstre, 



