16 INSECT PARASITES. 



On reaching their so-culled * full-fed ' state they get 

 into some crevice or amongst dust and dung, and 

 there spin themselves a pale silken cocoon, often 

 covered in dirt. 



In this cocoon the maggot changes into the pupal 

 or nymph state (fig. 3), the period of quiescence, 

 when the larva is k transformed ' into the distinct 

 adult. This pupa is at first quite pale in colour, 

 but by degrees its covering hardens and becomes 

 brownish ; the wings, feelers, legs, and eyes of the 

 future adult flea are now to be seen marked out 

 upon the pupal skin, closely folded and soldered 

 together. From ten to twentv-one days is the 

 length of time passed in this condition. At the close 

 of pupal life the shell, as it were, of the pupa, splits, 

 and from it there crawls the future active degenerate 

 little dipteron, destined to form a cause of great 

 annoyance to our poultry. 



The Hen-Flea breeds all the year round, but is 

 more productive in warm weather. It is very widely 

 distributed in Great Britain as elsewhere. 



Like most members of this extremely active family, 

 it will not live upon any but its own particular l host/ 

 That ' Hen-Fleas ' will settle upon us when we enter 

 dirtv hen-roosts of course is well known, but they 

 will not live, even if transferred to our houses. 

 Regarding their so-called bite, possibly some thin- 

 skinned people may suffer from them, but, as a 

 rule, they have little effect upon human beings. 



Regarding the food of the larva there is much 



