THE CONTAGIOUS TYPHUS OF THE OX. 141 

 I. 



Symptomatic Characteristics. The typhus of 

 the ox, like all infectious and contagious dis- 

 eases, offers to observation four successive 

 changes : 1st, a period of Incubation, during 

 which the original structure is subject to 

 internal and latent derangements ; 2nd, a 

 period of Initiation, during which the first 

 evident signs of the disease are manifested; 

 3rd, a period of Endurance, during which the 

 phenomena are fully developed ; 4th, a period 

 of Decline, or wasting atony. 



These divisions and classifications, it will 

 readily be conceived, are rather fanciful, for 

 nature does not adapt herself to our methodical 

 forms. Still we shall abide by them, because 

 they have their relative and practical utility, 

 and because they will afford to the practitioner 

 suggestions more easily understood; and finally, 

 because the organic changes are different at 

 these various periods, which in their entirety 

 constitute the typhus of the bovine species. 



The description of those different phases 

 through which the organism of cattle smitten 

 with the contagion has to pass, has moreover 



