714 



OPEEATIONS ON THE FOOT. 



and yellowish, which becomes hard and thick ; it is the hoof secret- 

 ed by the laminae, which, Httle by little, unites with that coming 

 from the coronary band. Excessive granulations or proud flesh 

 are removed in the ordinary way. 



D. Caktilaginous Quittoe. — Sufhnorpelfister (German) — 

 {improperly called sub-horny quittor, by Lafosse, Jr., coronary 

 quittor of Vitet;_/?6ro chrondritis of the third phalanx, by Vatel; 

 sub-horny cartilaginous quittor of Girard ; quittor proper of Del- 

 wart). This form of quittor is peculiar to solipeds, they being 

 the only animals which have fibro-cartUage on the os pedis. 



Fig. 523.— Cartilaginous Apparatus of the Hrrse's Foot, 

 a.— Lateral flbro cartilage. 6.— The superior bordPr. c— Its posterior border, d.— 

 Anterior lateral ligament, e. — Flexor tendons. /. — Extensor tendon, g. — Os pedis, 

 ft.— Ketrorsal process. 



These fibro-cartUages (Fig. 523) are two pieces, which, with 

 the plantar cushion, complete the os pedis and form the base of 

 the heels, each representing a piece flattened sidewise, a parallelo- 

 gram in shape, and extending posteriorly to the coffin bone. 

 Their external face is convex and pierced with foramina for the 

 passage of veias, and sHghtly overlies the surface of the bone of 

 the foot. It is separated from the skin by a very rich vascular 

 plexus. The internal face, concave, is hollowed by vascular 

 grooves, and covers (forward) the articulation of the foot and the 

 cul-de-sac of the synovial sac which protrudes between the two 

 lateral Hgaments of that joint. Downward and backward it is 

 united to the plantar cushion, either by contiauity of tissue, as 



