DISEASES OF THE SKIN AMONG DOMESTICATED ANIMALS. 37 
certain constitutional changes the nutrition of the skin and its 
power of resistance to traumata may be so lessened that the occur¬ 
rence of eczematous erruptions from external irritants is greatly 
favored. 
In spite of the multiformity of appearance of the disease in 
consequence of the violent scratching and rubbing, we can distin¬ 
guish three chief types of the malady. 
Tli q first type appears as small, irregular spots. The eruption 
begins as an eczema papillosum; the papules rapidly become 
vesicles, stadium vesiculosum; and this runs into the stadium 
madidans. The stadium crustosum follows less rapidly. 
The second type tends to spread peripherically. It begins as 
eczema papulosum. The isolated papules are scratched open, or 
change into pustules. They then form small crusts, under which 
the regeneration of the epidermis goes on. 
The third type is eminently disposed to become chronic. The 
short primary stages are usually overlooked, and a large surface 
of the diseased skin is found swollen, infiltrated, at first white 
and later covered with crusts which, in consequence of the 
scratching, are generally stained with blood. Later on the partial 
loss of hair, the thickening of the skin, and the marked epidermic 
desquamation alone remain. 
The treatment of eczema is greatly impeded by the impossi¬ 
bility of applying protective dressings, and of preventing the 
animals from scratching and rubbing themselves. 
After removing the causes and thoroughly cleansing the 
affected portions of skin, we may use : 
a. In the stadium papulosum and vesiculosum , cooling and 
protective salves (ung. zinci, plumbi, diachylon, hebr., prsecipi- 
tat. alb., salicylatum) or powders (zinc. ox. 1, amylum 5.) 
b. In the stadium madidans and impetiginosum , drying and 
astringent salves (nngt. tannic., plumbi tannici, acidi borici, 
(Gresswell); or powders (ac. salicyl. or iodoform with amylum 
or cort. quercus); or solutions (sol. argent, nitric. 1: 15, sol. 
hydrarg. bichlorat 1: 100 to 200.) 
c. In the stadium squamosum and in all chronic eczemas with 
much infiltration of the skin, alkaline soaps, concentrated solu- 
