DISEASES FROM FAULTY CONFORMATION 191 
of the animal to place the foot squarely on the ground. 
One is then led to manipulate the foot. The hoof is hot to 
the touch. Percussion causes the animal to flinch, and to 
flinch particularly when that portion of the wall adjoining 
the corn is struck. Finally, exploration with the knife 
reveals the serious extent to which the injury has developed. 
In a neglected case of this description it is even possible to 
detect the presence of pus by the amount of swelling and 
fluctuating condition of the coronet. The suppurative pro- 
cess has advanced in the direction of least resistance, and 
is on the point of breaking through the tissues immedi- 
ately above the horn. 
Lameness due to corn is oftentimes intermittent. With 
a simple corn, dry or moist, this intermission is largely 
dependent on the degree of dryness of the hoof or the road, 
and also on the character of the road surface. With a 
neglected, suppurating corn, on the other hand, variation 
in the degree of lameness, in addition to depending on 
circumstances such as these, is dependent to a larger 
extent upon the changes occurring with the suppuration. 
In this case the time of greatest lameness is immediately 
before the pus gains outlet. Immediately after its exit at 
the coronet the animal will go almost sound. Soundness 
continues so long as the opening at the coronet remains 
clear. The tendency, however, is for the opening thus 
made to quickly close again. Pus again accumulates, 
lameness arises as before, and disappears again with the 
second discharge of the contents of the sinus now formed. 
Pathological Anatomy.—When dealing with their classifi- 
cation we gave in outline the main pathological changes to 
be met with in corns. It now only remains to give the 
same matter in slightly greater detail. 
In dry corn the changes we meet with are those accom- 
panying blood extravasation. From excessive compression 
of the parts, or from the effects of direct injury, a portion 
of the sensitive sole has become lacerated. The escaping 
blood stains the surrounding soft tissues after the manner 
of blood extravasation elsewhere. If the escape of blood is 
