78 



FLEAS. 



The remedies used are local applications obnoxious 

 to the Fly, and careful attention to cleanliness. 



In some cases the head of 

 these Flies {pupipara) is so with- 

 drawn into the body, and the 

 horns into the head, that, in 

 addition to their sometimes being 

 without wings or poisers, they 

 have a spider-like appearance, 

 and are known as Spider Flies. 

 The MelojjJiagus ovi)ius, known, 

 though incorrectly, as the 

 "Sheep-tick," which lives in 

 the wool and sucks the blood of the sheep, is one of 

 this division. 



Those who wish to study its life-history and means 

 of prevention will find the information excellently 

 given in Dr. Cooper Curtice's ' Animal Parasites of 

 Sheep ' before referred to. 



Fig, 



62. — Sheep-tick, 

 magnified. 



FLEAS. 



The Aphamptera, or Fleas, have been scientifically 

 described as " Diptera " (that is, two- winged Flies), 

 " with laterally compressed body, and distinctly se- 

 parated thoracic rings." Whether this is precisely so 

 or not is perhaps not very important in the present 

 considerations. 



The general appearance of our common Flea is well 

 known ; but if examined under a magnifying-glass it 

 will be seen that there are some peculiar points in its 

 structure. The insect is not noticeably divided like 

 most others, but formed of a series of rings from the 

 head to the tip of the tail. It is to all practical pur- 

 poses wingless, but at the base of the 2nd and 3rd 

 segments from the head there is on each side a small 

 scale. These two pairs of scales are considered to 

 represent the two pairs of wings that most insects 



