HORN. 515 



fibres run in a parallel direction, and in a straight line from 

 the papillae which form them. Thus the papillae on the 

 coronary band, frog, and vascular sole, are all directed down- 

 wards and forwards. 



If a hoof is cut through perpendicularly, it is found that the 

 deeper layers are soft, and the tissue becomes progressively 

 harder from within outwards, so that the surface is firm 



Fig. 217. (CHAUVEATJ.) Longitudinal section ot four horn fibres of the wall, taken 

 from the point of union between the white and dark horn. The dark material in the 

 centre of the fibres is composed of opaque spherical cells, which appear dark when seen 

 by transmitted light. 



and of a character suited to its functions, viz., for sustaining 

 weight, maintaining a given form, and defending from injury; 

 at the same time, it is endowed with, elasticity, one of the 

 essential properties of hoofe. 



The so-called horny fibres are funnel-shaped at the point 

 of connection with their respective papillae. Each fibre has 



