88 OUTLINES OF EQUINE ANATOMY. 



forwards, wliicli form a continuous articulatory surface 

 for tlie patella to play over. The inner is mucli tlie largest, 

 especially suj^ero-anteriorly, where it becomes bulbous, with 

 an inclination inwards. The outer decreases slightly in 

 size posteriorly. The non-articulatory parts of these ridges 

 are rough for attachment of the capsular ligament of the 

 stifle. The ijosterior part of the inferior extremity consists 

 of two condyles separated by the intercondyloid fossa, 

 which runs from behind forwards. It is roughened for 

 attachment at its postero-internal part of the postero- 

 superior ligament of the outer interarticular disc of car- 

 tilage. Just in front of this the outer condyle is under- 

 mined for attachment of the superior extremity of one 

 crucial ligament, while the inner similarly affords attacil- 

 ment to the other. Anteriorly are numerous foramina. 

 The outer condyle is the largest, and in front of its inferior 

 extremity is a deep depression, whence arises the common 

 tendon of flexor metatarsi and extensor pedis. Behind an^ 

 above this is a ridge running backwards, to the anteria* 

 part of which the tendon of popliteus is attached, to ths 

 posterior parts the outer lateral ligaments of the patella, 

 and of the stifle joint. The inner surface of the interna}, 

 condyle is roughened, and presents a prominence to which 

 are attached the corresponding inner lateral ligaments. 

 The articulatory surface of the inner condyle is continuous 

 with that of the inner ridge. 



PATELLA is a floating bone, situated at the infero- 

 anterior part of the femur. It is the " knee cap " of the 

 human subject, and has three surfaces and three angles. 

 The superior surface looks slightly backwards, it is bicon- 

 .cave (slightly) affords attachment to triceps cruralis, and 

 is bounded anteriorly by a prominent margin, posteriorly 

 by a line, convex externally, concave internally. These 

 meet at a rounded angle outwardly, from which run the 

 outer patellar lateral and straight ligaments, and at an acute 

 angle inwards, where the bone is continued by a fibre -car- 

 tilaginous prolongation, from the extremities of which pass 

 the inner lateral and inner sti'aight patellar ligaments. The 

 cmtenor surface is rough and convex, affording attachment 

 outwardly to triceps abductor femoris. Its superior mar- 

 gin is rounded. Its inferior margin comes to a point cen- 

 trally ; just above this is a smooth spot for a bursa and 

 still higher up is roughened for attachment of the central 



