36 THE BOOK OF THE FLY 



honey bee, to pass out very little anal excreta ; some have 

 thought that, like what is said of bee larvae, no excre- 

 ment is discharged until after the imago has emerged 

 from the puparium ; but such conduct seems altogether 

 incredible. In the bee-hive doubtless the assiduous 

 workers ever wash their babies clean and lick up all 

 matter, just like domestic cats and dogs, when nursing 

 their young. 



The larva of the blue-bottle, called a gentle, is pro- 

 portionately larger but very similar, except that the 

 rear segment possesses a ring of tubercles, which may 

 have some useful function in connection with two 

 breathing tracks, which have their orifices at that part 

 of the body. 



The larva of the lesser house-fly is very peculiar ; 

 all its segments have projecting tubercles ; its whole 

 body is rather louse-shaped, having not cylindrical 

 but somewhat flattened segments, of which the middle 

 are the broader, and those near the head and tail the 

 narrower. 



The transformations in the case of the blue-bottle 

 are typical of the house-fly and others of closely related 

 families and genera which are many-brooded within 

 the year; these creatures develop very rapidly immedi- 

 ately after emerging from the egg. Some other kinds 

 of dipterid maggots, which are single-brooded, pass a 

 very prolonged and obscure early period of skin- 

 shedding and non-feeding, a preparatory sort of baby- 

 hood metamorphosis ; then at last they begin to feed 

 voraciously and to follow the general habits of other 

 maggots. Some maggots curiously refuse to feed 

 except in company ; probably some are unable to feed 



