ARTICULATIONS OF THE ANTERIOR LIMBS. 



211 



its inferior face by the skin of the interdigital Bpace. Its upper face is in contact with an 

 adipose cushion. 



In the Ox, the external anterior lateral ligament, wide and expanding, is almost entirely 

 covered by the long branch of the proper extensor of the digit, to which it is intimately 

 adherent. The interdigital ligament has a much more complicated character than that of the 

 Sheep. It is formed of fibres intercrossed on the median line, and divided at its extremities 

 into two fasciculi : a superior passes over the perforans tendon, to which it serves as a restrain- 

 ing band, and is fixed to the outside of the inferior extremity of the first phalanx, after con- 

 tracting very close adhesions with a strong fibrous web which descends from the posterior 

 metacarpal region, and which will be more fully noticed when describing the muscles; an 

 inferior, shorter than the preceding, attached to the internal extremity of the navicular bone 

 and the internal face of the third phalanx, becoming confounded with the perforans tendon, 

 the plantar cushion, and the dermis of the keratogenous membrane. 



Fig. 138. 



Fig. 137. 



JffJO i 



LONGITTIDrNAL AND VERTICAL SECTION OF THE 

 DIGITAL REGION IN THE HORSE, SHOWING THE 

 ARRANGEMENT OF THE ARTICULAR AND TENDI- 

 NOUS SYNOVIAL APPARATUS. 



1, First phalanx ; 2, second phalanx ; 3, third pha- 

 lanx ; 4, semilunar sinus of ditto ; 5, navicular 

 bone ; 6, tendon of the anterior extensor of the 

 phalanges ; 7, its insertion into third phalanx ; 8, 

 tendon of the perforatus ; 9, ditto perforans ; 10, 

 its insertion into the third phalanx; 11, inferior 

 sesamoid ligaments ; 12, posterior ctd-de-sac of 

 the first synovial interphalangeal capsule; 13, 

 ditto of second ; 14, infeiior cul-de-sac of the 

 sesamoid bursa; 15, superior ditto of navicular 

 bursa ; 16, inferior ditto of same ; 17, station of 

 the coronary cushion; 18, ditto of plantar 

 cushion. 



TENDONS AND LIGAMENTS OF 

 THE POSTERIOR FACE OF 

 THE DIGITAL REGION OF 

 THE OX. 



1, Perforatus tendon ; 2, 2, 

 its terminal tendons ; 3, 



3, theii- bifurcation ; 4, 



4, perforans tendon ; 6, 6, 

 superior branches of the 

 inferior interdigital liga- 

 ment attached to the first 

 phalanx ; 7, inferior inter- 

 digital ligament ; 8, 8, 

 suspensory ligament of 

 the fetlock. 



In the Pig, for the maintenance of the second interphalangeal articulation, there are: 

 1. Two lateral ligaments, carried from the lateral faces of the second phalanx to the external 

 and internal faces of the third. 2. A third ligament, exactly resembling one of the posterior 

 lateral ligaments of the pedal articulation of the Horse; this ligament descends from the 

 inferior extremity of the first phalanx to the internal extremity of the navicular bone. Its 

 analogue of the inner side appears to be altogether absent ; but in the large digits there is an 

 anterior yellow elastic ligament like that of Ruminants. 



In the Dog, the two last phalanges are united by two lateral ligaments, very simply 

 arranged. A third ligament, formed of elastic tissue, divided into two lateral portions, and 

 situated in front of the articulation, plays the part of a spring, which mechanically produces 

 the retraction of the claw when the flexor muscles cease to contract. In the Cat, this yellow 

 ligament is very strong; and this animal also exhibits a very striking obliquity of the articular 



