PRACTICE OF VETERINARY MEDICINE. 
561 
tween them and haemorrhage from mucous surfaces, and others 
being almost identical with scurvy. Purpura usually appears in- 
dependently of fever, with a number of reddish, purplish, or livid 
spots, of various sizes, on the cutaneous surface, these spots being 
usually termed PETECHIiE, vibices, and ECCHYMOSES, according to 
their sizes ; and, in the severer cases, it is attended by haemorrhage 
from one or more surfaces, but chiefly from the mucous surfaces. 
The spots or patches are rarely elevated above the surrounding 
level of the skin, are not attended by any uneasy sensation, and, 
when examined closely, they are found to consist of exudations of 
blood between the layers of the dermis, or in the subjacent cellular 
tissue, or rather serum coloured by the red globules variously 
altered. They cannot be viewed as an eruption or rash, but are, 
strictly, a passive haemorrhage of the vascular tissue of the 
skin.” 
According to Dr. Copland, purpura in the human subject “ usu- 
ally appears independent of fever;” a fact which is not borne out 
with reference to this disease in the horse, at least so far as my 
own experience has gone. In every case which I have recorded, 
more or less fever was present when the malady became recognized; 
indeed I can scarcely suppose that such an extensive morbid 
change could take place within the system without fever manifest- 
ing itself simultaneously : nevertheless, I am prepared to admit that 
the fever might be so slight (as in Case V, for instance) as not to 
excite the attention of non-professional observers. In the cases 
given by my friend Mr. Moore, he considers the disease to be 
erysipelas, from the fact, no doubt, of its spreading so rapidly : in 
this view of the matter Mr. Moore is mistaken. Erysipelas, as its 
name implies, is an inflammation of a spreading character, and one 
which confines itself chiefly to the skin and to its immediate sub- 
textures ; but purpura is not a disease of the skin at all, and, so 
far from its being essentially an inflammatory one, it frequently 
occurs in states of the system of decidedly an opposite nature to 
that which is described as such. It appears to me, in short, to be 
altogether peculiar in its nature ; the most remarkable feature of 
it consisting in the strange morbidly debilitated state of the entire 
circulatory system, thereby, as Dr. Copland expresses it, “ per- 
mitting the passive exudation * of the blood into the mucous , muscu- 
lar, serous , and cellular tissues of the body. 
Predisposing and exciting Causes of Purpura. — The most 
prolific predisposing causes of purpura are those which morbidly 
debilitate the vital energies; indeed, this may be said of all dis- 
eases; but the kind of disease which may result will undoubtedly 
depend either upon some peculiar predisposition in the organism 
