SHOEING. 



581 



4. An elastic fibro-cartilaginous process ; the plantar cushion 

 attached to the third phalanx, which it complements behind, and 

 enlarges the surface by which it takes its bearing on the sole, and 

 transmits to the ground the pressure which it supports. It is 

 the means of deadening shocks and reactions. 



5. Arteries, veins, and lymphat- 

 ics, vessels which contribute to the 

 nourishment of the foot, and are 

 remarkable by their number and 

 their flexuous and anastomotic dis- 

 position. See Figs. 371, 372, and 

 others farther on. 



6. The nerves, the organs of 

 sensibility in the foot, also remark- 

 able for their number. 



7. An integumental membrane 

 peculiar to the region of the foot, 

 and differing from the general in- 

 tegument, or skin, of which it is a 

 continuation, by its external ap- 

 pearance, its modified structure, 

 and its special functions ; thus it 

 is this membrane which secretes 

 the horny case or hoof, but as- 

 sumes a particular appearance ac- 

 cording as it is required to secrete 

 the anterior and lateral face or 

 wall, or the lower face or sole. At 

 the height of the second phalanx 

 it forms a thick circular pad which, 

 released from the horn which hides 

 it, displays the form of a rosy mem- 

 brano covered with an infinite 

 number of little short filaments, 

 thick as those of velvet. These 

 form the matrix of the horn, and 

 are true hair-roots, for the horn is 

 nothing but a great quantity of 

 threads or hairs attached one to 



FIG. 366. Posterior view of front 

 digital region. 



1. Large metacarpal bone; 2, 3. 

 Outer and inner splint bones; 4, 5. 

 Sesamoid bones; 6. Suffraginis; 7, 

 8. Tuberosities for insertion of cru- 

 cial ligaments; 9. Triangular space 

 for insertion of short sesamoid lig- 

 ament; iO. Anterior face of suffra- 

 ginis; 11, 12. Tuberosities for liga- 

 mentary insertion ; 13. Articular de- 

 pression separating condyles; 14, 

 15. Second phalanx; 16. Scabrous 

 surface for ligamentous attachment; 

 17. Smooth surface for gliding of 

 deep flexor tendon; 18. Navicular 

 bone; 19. Pedal bone; 20. Basilar 

 process; 21. Plantar foramen. 



