48 LIGAMENTS AND MUSCLES OF THE HORSE. 



the posterior common ligament of the knee, outwardly, by 

 the trapezium, and posteriorly by a strong fibrous band, ex- 

 tending from the trapezium to the inner side of the carpus. 

 This sheath is lined by a synovial membrane, which is re- 

 flected on the flexor tendons ' it extends two or three 

 inches above the knee, and downwards to the middle of the 

 metacarpus. 



Sesamoid Sheath. 



The synovial membrane of this extends two or three inches 

 above the fetlock, and downwards till it meets the navicu- 

 lar sheath. 



(When distended, it bulges upwards, forming the condition 

 known as wind-gall.) 



Navicular Sheath (or bursal 



This facilitates the play of the perforaiis tendon over the na- 

 vicular bone. It extends above the navicular bone to meet 

 the sesamoid sheath. 



METACARPAL REGION. 



1. Interossei (2) ] . 



^ ^ , . . ,„' Very small and ummportant. 



2. Lumbrict (2) J "^ 



1. Interossei. 



Origin. — Near the head of the small metacarpal. 

 Insertion. —To the bifurcation of the suspensory ligament. 

 Action. — Inappreciable. 



2. LUMBRICI. 



Origin. — From the deep flexor tendon above the fetlock. 

 Insertion. —To the fibrous basis of the ergot. 

 Action. — Inappreciable. 



GLUTEAL REGION. 



1 . Ghiteus exttrnus (superficial gluteus . 



2. Gluteus maximus (middle gluteus . 



3. Gluteus internus (deep gluteus). 



