KNEE. 



281 



undue extension of) the fetlock joint, namely, the sus- 

 pensory ligament, flexor tendons and check ligament. 



We are indebted to Mr. R. C. Irving, F.R.C.V.S., for 

 explaining that congenital ''standing over at the knees" 

 is due to deficient development of the muscles which 

 straighten the knee (extensor metacarpi magnus and ex- 

 tensor metacarpi ohliqims vel parvus), and which are on 



Photo bij] 



Fig. 351. — Mrs. Hayes's Salary. 



[M. H. H. 



the front of the fore-arm. This relatively poor develop- 

 ment of the muscles on the front of the fore-arm is 

 well shown in Fig. 422. It is possibly caused by a 

 portion of the contractile tissue being replaced by fibrous 

 tissue, in which case, the contractile power and volume 

 of the muscles in question would be diminished. 



The fact of a horse being "calf-kneed" renders the 

 back tendons and check ligaments more liable to sprain by 

 violent descent of the fetlock, than if the knee were 

 straight. It tends, however, to make the animal more 



