586 



THE COMPLETE GRAZIER. 



BOOK VI 



have been placed, retain their contagious properties for some time. If 

 the weather be hot and dry the acari left behind suffer from shrivelling 

 up and dtying, and from three to eight days are required to destroy 



Fig. 152. Acari in Various Stages of Development, Intermingled with Wool 



and Masses of Scab. 



a. Mature tenialc acarus lying in a mass of scab. 



b. Young acarus after change of skin. 



c. Cast-off skin ot an acarus. 



d. Ovum, with the yolk contracted. 



e. Ovum, containing a young acarus. 



/. Ovum, with young acarus in the interior about to be hatched. 



Drawn with the camera. Magnified 60 diameters.) 



them effectually ; but if the atmosphere be moist and warm, they Avill 

 retain their vigour and activity even after a much longer period. 



FOOT ROT consists primarily of an inflamed condition of the sensitive 

 tissues contained within the hoof. Writing of this disease, Professor 

 Axe says that animals having a thin supple skin and a fleece of fine 

 texture are most liable to it, and possibly for the reason that the hoofs 



