284 DISEASES OF THE HORSE’S FOOT 
toe, takes on an increased growth. The same thing we 
have already indicated as happening at the toe, though in 
lesser degree. Taken together, this increased growth. of 
horn at the toe and at the heels has the result of lengthen- 
ing the diameter of the foot from before backwards, the 
transverse diameter remaining more or less normal. The 
hoof thus loses its circular build, and comes to approach 
nearer an elongated oval. 
At this stage, too, the pathological ‘ ribbing’ of the hoof 
is observable. The outer surface of the wall becomes 
marked with a series of ridges encircling the hoof from 
Fic. 122._FooT BADLY DEFORMED AS A RESULT OF CHRONIC 
LaMINITIS, 
heel to heel (see Fig. 81, which illustrates a moderate 
deformity of the hoof occurring after laminitis). In the 
badly laminitic hoof, however, this deformity is largely 
increased, until in some cases the shapeless mass can 
hardly be likened to a foot at all (see Fig. 122). 
The inferior or solar surface of the foot also offers certain 
changes for our consideration. The first thing that strikes 
one is the convexity of the sole. This, as we have already 
pointed out, is due to descent of the os pedis, and the 
highest point of the convex portion is that immediately in 
front of the apex of the frog. Here the horn is sometimes 
found to be quite yielding to the finger, is excessively thin, 
