628 ACUTE LAMINITIS, ENTERITIS, AND PNEUMONIA. 
fibrin, but the microscope and chemical tests showed it to be 
composed of rudimentary horn. The villi of the coronary 
substance could be traced by the microscope into the horny 
tubes of the hoof, and did not exhibit any material increase 
of vascularity. The synovial membranes and their fringes 
inside the hoof, and behind the pastern, appeared healthy. 
Inflammation seemed confined to the laminated structure 
outside the coffin bone. We have often noticed in dissec- 
tions made in cases where death occurred early in this 
disease, through thoracic or abdominal complications, that 
young horn begins to form as soon as exudation has separated 
the crust from its natural connexions. In unusually acute 
laminitis, the coronary margin of the hoof becomes detached 
also, but in the majority of instances such separation does 
not occur. In the ordinary run of cases, where separation 
does occur, I am inclined to think from this and numerous 
other dissections, that the horny and sensitive laminae are 
disunited sooner than is generally supposed. In the above 
case the feet were cooler and less painful on the 20th, that is, 
after 24 hours of acute illness. My own idea is, that sepa- 
ration of the hoof had then occurred, because the mare never 
stood afterwards, and the feet were by no means unnaturally 
hot from that time. Then, again, the actual formation of 
new horn upon the sensitive laihinae must have required some 
time, and the only remaining period between this and death 
was something like 30 hours. We have, at all events, the 
following facts: — 1. The crusts of the hoofs were detached 
from the internal parts by inflammatory exudation. 2. New 
horn was formed upon the free margins of the sensitive 
laminae, and between their lateral surfaces, so as to unite them 
firmly. 3. The period within which these processes took 
place was certainly less than 72 hours. 
It is probable that laminitis was not the immediate cause 
of death, because — 
1. There was apparently sufficient pulmonary disease to 
produce a fatal result ; this was accompanied by 
2. A considerable amount of enteritis. 
3. Laminitis alone rarely destroys life in three days. In 
cases of laminitis, so severe as to induce sloughing of both 
fore hoofs, the patient has not died of the disease ; and in- 
stances have been known where all the four hoofs were 
sloughed, and the horses recovered. 
Many cases of laminitis (especially in draught horses), arise 
from over feeding, from feeding on indigestible food, or from 
intestinal irritation produced by other causes. A number of 
horses, for instance, have got out of their grass pasture into 
