DISEASES OF THE OX AND SHEEP. 593 



columns and columns on new drugs and appliances of yet more 

 paramount importance. There are others of still higher signi- 

 ficance than is hydrochlorate of cocaine, and it may be said, 

 without the least shade of a fear of contradiction, that, if the 

 science of medicine continues to progress in the course of the 

 next fifty years as it has undoubtedly progressed in a wondrous 

 degree during the last half century, our successors will indeed 

 have good reasons to congratulate themselves upon the immense 

 powers they will be able to wield over the insidious yet 

 manageable onsets of disease, and the premature threatenings 

 of the clutches of the ghastly monster, death. 



Assuredly, we have no hesitation in affirming that the same 

 sciences, in so far as they bear upon the disorders of lower 

 animals, have in like manner made rapid and sure ascents up the 

 steep and arduous hill of discovery ; and it may be also very 

 appositely advanced that there are some cases in which these 

 latter acquisitions have helped on the knowlege possessed by 

 those whose avocation is that high and ennobling one, the cure of 

 human disease and the alleviation of human suffering. As years 

 roll on, veterinary science must and will occupy one of the 

 highest positions, and those who are engaged in it will be fully 

 and adequately recoguised as workers in the great cause of science 

 at large. 



MANGE.* 



The disorder known under the appellation of mange is con- 

 tagious, and due to the presence of a minute acarus in numbers 

 on the skin, and to the ravages produced by their burrowing 

 their way from the surface into the cuticle. 



According to Gerlach there are two forms, viz. the Dermato- 

 dectes hovis and the Symhiotes bovis, of which the latter is rare 

 and the former frequent. Our readers will understand that the 

 mange-spider of the ox is different from that of the horse, from 

 that which causes sheep-scab, and also from the Acarus scahiei 

 of man. In short, each animal is liable to be infested with 

 its own peculiar acarus living parasitically upon the skin, and this 

 acarus cannot become parasitic upon the skin of another animal, 

 though it will maintain vitality for a time. The Dermatodectes 

 of the ox is very frequently first found upon the withers and the 



* Scabies is mentioned under " Parasitism," see pages 437 to 447. 



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