43 



kinds of insect parasites of domestic animals has yet to be tried in de- 

 tail, its importance in this field has already been demonstrated. 



Preventive treatment, — The sheep should not be turned into the old 

 pens or pastures until a week after the first dip, by ■^hich time it may 

 reasonably be supposed that all parasites on the ground have died. To 

 avoid the chance of any recently hatched parasites getting from the 

 ground to sheep in places where the sheep rest, it is best to scrape out 

 and cleanse the pens. Animals recently purchased should always be 

 dipped before being added to the older flock. 



By following out a thorough plan of treatment, and by carefully 

 guarding the sheep from re-infection, the flockm aster should be able to 

 rid his flocks of this pest in a single season. 



