25 



PECULIAR PROPERTIES OF THE FROG. 



The substance of the horny frog is eminently elastic, and 

 .corresponds in the closest manner to the dense elastic epider- 

 mic pads on the soles of the feet of such animals as the camel, 

 elephant, lion, bear, dog, cat, etc. ; and which are evidently 

 designed for contact with the ground, the support and protec- 

 tion of the tendons that flex the foot, to facilitate the springing 

 movements of these creatures, and for the prevention of jar 

 and injury to the limbs. In the horse's foot, the pressure of 

 this thick, compressible and supple mass of horn at the back 

 of the hoof, in a healthy unmutilated condition, and permitted 

 to reach the ground while the animal is standing or moving, 

 are absolutely essential to the well-being of that organ, more 

 especially should speed, in addition to weight-carrying be 

 exacted. 



' The frog like the sole exfoliates, or becomes reduced in 

 thickness at a certain stage of its growth; the flakes are more 

 cohesive than those of the sole. 



THE INTERNAL APEX OF THE HORNY FROG. 



It must be remarked, however, that this exfoliation of the 

 sole and frog only takes place when the more recently formed 

 horn beneath has acquired sufficient hardness and density to 

 sustain contact with the ground, and exposure to the effects of 

 heat, dryness and moisture. 



The cleft of the frog penetrates some distance into the foot 

 and terminates in a horny prominence which I am accustomed 

 to regard as the internal apex. This prominence, by its pointed 

 character and upward direction when one or both heels are 

 contracted or shrunken and the frog is of small dimensions, 

 plays a very important part in the production of lameness. 

 This, however, I will not dwell upon here. 



A REMARKABLE APPENDAGE TO THE FROG. 



The frog-band or stay was first dissected out and described by 



Bracy Clark. Mr. Fleming designates it by the more technical 



c 



