318 DIABETES INSIPIDUS. 



has operated in the production of a dietary unfit for sustain- 

 ing healthy activity in connection with the many steps in the 

 process of assimilation. Certain plants, and forage which 

 contained these plants, have often been accredited with the 

 production of this condition. This I have not observed, but 

 rather have I found it to develop in connection with the con- 

 sumption of various fodders and foods when damaged by bad 

 harvesting, or where vegetable fungi have largely taken posses- 

 sion of it. 



During convalescence from many debilitating diseases it is 

 not unfrequently observed that a very trifling error in dieting, 

 either as to quantity or quality, will so operate as to develop 

 the condition of polyuria, the attack generally passing oft" 

 when the indigestion which induced it has passed away. 



Of causes operating from within, and Avhich, when fully de- 

 veloped, are more likely to terminate unfavourably than those 

 which are brought directly to bear on the animal from with- 

 out, the chief are excessive tissue-disintegration and imperfect 

 food-assimilation. These conditions may again be regarded 

 merely as the sequelae of some antecedent and further removed 

 operating agency ; they may follow the attack or recovery 

 from some other diseased condition, or they may result from 

 undue exposure to adverse atmospheric conditions, or from 

 long-continued and exhausting work. 



The products of the excessive tissue-change not onl}- 

 morbidly influence these excretory organs, the kidneys, 

 through which they are naturally removed from the system, 

 but in their entrance into the blood and l3='mph-channels 

 induce, through their universal distribution, disturbance and 

 perversion of power in many, if not in all, the systems of 

 the body. 



Anatomical Features. — In animals which have died directly 

 from the effects of the disease, as also in others where death 

 has occurred from other causes while the animals were suffering 

 from an attack of polyuria, the lesions observed have neither 

 been numerous nor diagnostic. These, when present, are chiefly 

 in connection with the muscular and glandular systems. 



In the muscular system we observe want of colour and an 

 unnatural, soft and flabby condition ; in the great glands of 

 the abdomen there is the same general characters, particularly 



