42 EQUINE ANATOMY. 



Keratogenous membrane, resting upon a fibrous 

 fascia and covered by the lioof. It is composed of the 

 coronary cushion, the velvety and laminal tissues. 



Coronary tissue, bourrelet or cutidura. — It is 

 lodged in a cavity at the upper border of tlie horny 

 case. Its inferior border is separated from the 

 laminae bj a white zone ; the superior border is limited 

 by the perioplic ring; its extremities are reilexed near 

 the bulbs of the plantar cushion into tlie lateral lacu- 

 nae of the pyramidal body ; its surface is covered 

 with papillae, villi and villous loops ; its structure is 

 the same as the cutaneous derma, is very vascular 

 and has many nerves ; it is red, and sometimes macu- 

 lated black by pigment. 



Yelvety tissue covers tlie plantar snrface of the 

 OS pedis and the plantar cusliion. Its surface is like 

 those upon whicli it rests, having a central and a periph- 

 eric portion covered by the sole. It is provided with 

 numerous villosities, received in the porosities of the 

 sole and frog, and has the same structure as the cuti- 

 dura, 



Laminal or podophyllous tissue. — This covers the 

 anterior face of the os pedis. It consists of five or six 

 hundred laminai, parallel, wider below than above, den- 

 ticulated on their free border, and having folds on 

 their lateral surfaces ; they are received between the 



