140 



THE BONES. 



is nearly obliterated ; that the trochantir has subsiiled nearly to a level with the articulaJ 

 head; and that the trochha is circumscribed by two equal-sized lips. 



The femur of the Camel more nearly resembles that of Man. It is long, slender, and curved 

 backwards. The body is prismatic in its middle portion, and the two branches of the linea 

 aspera meet in the middle and diverge towards the ends. Tlie articular head is very much 

 separated from the trochanter major, which is below the level of tlie most prominent part of the 

 head. Tiie internal condyle is smaller than the external, and the trochlea is narrow, while its 

 lips are equal. 



B. Pig. — In the femur of the Pig, there is also noticed a supra-condyloid fossa, but it is 



wide and sliallow ; the rugosities of the posterior face are replaced by some salient lines ; the 



trochanter major is on a level with the heail; the latter is supported by a somewhat constricted 



neck,andissituated within, and in front of, the trochanter major. This hitter disposition changes 



the direction of the great axis of the superior extremity, 



which fibliquely crosses that of the inferior extremity. 



C. Camivora. — In the Dog and Cat, the femur is 

 long and curved like a bow. Tlie rugged surfaces of the 

 posterior face are confounded, and form two crests repre- 

 senting the linea aspera of the human femur. These 

 crests do not lie against each other in the middle portion 

 of the bone — they are merely parallel ; tlien they diverge 

 above and below, to terminate beneath the great and 

 small trochanters, and above the two condyles. The 

 trochanter major is not so high as the particular head. 

 The femur of Carnivora is also distinguished: 1. By 

 the complete absence of the third trochanter and the 

 supra-condyloid fossa — this last being replaced by a 

 small tubercle, which terminates below the external 

 brinch of the linea aspera. 2. By the marked constriction 

 and length of the neck supporting the articular head. 

 3. By the depth of the digital fossa. 



In the Cat and Rabbit are found small bony nodules, 

 embedded like sesamoids m the substance of the lateral 

 ligaments of the femoro-tibial articulation. After mace- 

 ration, liiey often adhere to the condyles of the femur. 



D. Rodents.— The femur of the Rabbit resembles 

 that of the Dog. It is flat before and behind, and more 

 bent inwards at its upper end. The internal trochanter 

 appears as a crest, and not a tubercle ; and the sub- 

 trochanteric crest is very developed, and placed im- 

 mediately below the trochanter major. 



Leg. 



This has for its base three bones : the tibia, 

 peroneus {pv fibula), and the rotiila {or patella). 



A. - B 



rEMtJR OF THE OAT AND RABBIT. 



L, Femur of the Rabbit. B, Femur 

 of the Cat. 1, Diaphysis ; 2, head ; 

 3, internal trochanter; 4, trochanter 

 major ; 5, subtrochanteric crest ; 

 6, trochlea; 7, internal condyle; 

 8, sesamoid imbedded in the internal 

 ligament of the femoro-tibial articu- 

 lation. 



1. Tibia (Fig. 93). 



The tibia is a long prismatic bone, thicker at the superior than the opposite 

 extremity, and situated between the femur and the astragalus, in an oblique 

 direction downwards and backwards, constituting the principal portion of the 

 leg. It has a body or shaft, and two extremities. 



Bod//.— Thk offers for study three faces and three borders. The faces are 

 wider above than below. The external is almost smooth, and is concave in its 

 superior part and convex below, where it deviates to become the anterior. The 

 internal, slightly convex on both sides, presents, superiorly, deep imprmts for the 

 attachment of the adductor muscles of the thigh and the semitendinosus. The 

 posterior, nearly plane, is divided into two triangular surfaces : one, superior, 



