A CONTRIBUTION". 
141 
favor the entrance of contagions elements into the system. "Why 
pustules similar to those of the other forms of variola? do not de¬ 
velop on the pasterns of the horse, probably lies in the anatomical 
construction of the relatively thick cutis of the parts in question. 
I lately inoculated a calf upon the ear with humanised vaccine, 
and there developed upon the same an eczema, but no pustules; 
while a calf inoculated shortly after (by Dr. Kranz and myself) 
upon the udder and valva presented well developed vaccine 
pustules. 
The same reasons which we have brought forward in consider¬ 
ing the descent of v. pocina from other variolic forms, also lead 
me to consider the idiopathic development of v. equina as very 
doubtful. Entirely discarding an abiogentic origin, I must con¬ 
sider other springs as the fountains from which this so seldom 
(by us) appearing disease takes its origin. Bouley’s assertion 
that v. equina is much more frequent than the original v. vaccina 
is even for France scarcely justifiable, as far as we can judge from 
the present literature, and not at all applicable to Germany. As 
it has been experimentally proven, that horses are susceptible as 
well for animal as for humanised vaccine, also for human variola, 
it seems scarcely necessary to go farther in seeking for the genesis 
of v. equina. We have already considered Scholz’s observations 
with regard to the transmission of v. humana by diseased attend¬ 
ants to foals. Tlpit v. vaccina (bovina) cannot possibly owe its 
genesis to v. equina, is sufficiently proven by the simple fact, that 
v. vaccina comes to pass in all parts of Germany, while v. equina 
seems to almost entirely fail of representation. 
Variolce caprinoe is also a very seldom disease, for in the 
course of ^0 to 30 years we can scarcely find a description of half 
a dozen cases. It comes to pass in two different forms : as a local 
process—similar to v. vaccina—upon the udder, and also as a gen¬ 
eral exanthema, accompanied by fever. As a localized affection, 
the caprine form evidently corresponds to the bovine, and presents, 
like the same, an irregular development; and either proceeds from 
the same, or has a like origin. Although we find here and there 
assertions that the same form of variola have been met with co- 
evially by goats and cows, yet goats, as a rule, remain exempt 
