THE POSTEBIOR LIMBS. 



151 



Comparison of the Abdominal Limb of Man with that of Animals. 



A. Pelvis (Fig. 103). — The longitudinal axis of the pelvis of Man forms, with the horizon, 

 an angle of about 40°. 



The bones which compose it are proportionately larger and stronger than in all the 

 domesticated animals. 



The two faces of the ilium, and especially the inner face, are much hollowed ; the iliac 

 crest has the form of an italic S. 



The pubis alone participates in the formation of the pelvic sympliysis, and the concavity 

 which, in the domesticated animals, 



is called the ischial arch, is desig- Fig. 103. 



nated in Man the pubic arch. 



In consequence of the excavation 

 on the inner face of the ilium, the 

 pelvic cavity may be divided into 

 the great and lesser pelvis. In the 

 latter are lodged the genital and 

 urinary organs, as well as the ex- 

 tremity of the digestive tube. 



B. Thigh (Fig. 104).— The femur 

 of Man is nearly vertical, and situ- 

 ated in a direction sligiitly oblique 

 downwards and inwards ; it presents 

 a curvature forwards. The body of 

 the bone is prismatic and triangular 

 in its middle part; the posterior 

 border of this prism forms a some- 

 what salient cresf, which takes the 

 place of all the insertion eminences 

 on the posterior aspect of the femur 

 in animals, and is designated the 

 linea aspera. This line bifurcates 

 above and below ; below, the branches 

 margin a triangular or popliteal space. 



The head is supported by a long 

 neck, inserted obliquely into the 

 superior extremity. The two con- 

 dyles are joined together in front by 

 the trochlea, which is wide and* 

 shallow. 



a Leg (Fig. 105) —Three bones : 



human pelvis (female). 



1, Last lumbar vertebra ; 2, 2, intervertebral substance ; 

 3, promontory of the sacrum ; 4, anterior surface of the 

 sacrum ; 5, coccyx ; 6, iliac fossae ; 7, antero-superior 

 spinous process ; 8, antero-inferior spinous process ; 

 9, acetabulum, a. Its notch ; 6, body of ischium; c, its 

 tuberosity ; d, its spine ; e, pubis ; /, symphysis pubis ; 

 g, arch of the pubes ; h, angle of os pubis; i, spine of 

 pubes, with crest between it and h; k, k, pectineal line ; 

 I, I, ilio-pectineal line, with its prolongation, m, m ; 

 n, ilio-pectineal eminence ; o, smooth surface for femoral 

 vessels ; p, p, great sacro-ischiatic notch. 



the tibia, fibula, and patella. 



The tibia is very long ; its crest (or spinous process) is much more developed than in any 

 of the domesticated animals, and describes a kind of curve like an italic S. On the inner 

 aspect of the inferior extremity is seen a voluminous process which occupies, inwardly, a 

 portion of the tibio-tarsal articulation : this is the internal malleolus. The articular surface ia 

 not exactly formed to correspond with the whole articular surface of the astragalus. 



The fibula is as long as the tibia. It is prismatic, and slightly twisted on itself. It articu- 

 lates above and below with the tibia. The lower extremity responds to the astragalus, and 

 forms a prominence named the external malleolus. 



There is nothing particular to note in the patella. 



D. Foot (Fig. 106). — The foot of Man is pLaced in a horizontal direction. Its upper 

 aspect is convex; its inferior face is excavated, and it rests on the ground by its two 

 extremities. 



1. Tarsus. — In the tarsus there are seven bones, three of which are cuneiform. The astra- 

 galus articulates with the tibia and fibula ; it responds to the scaphoid by a well-detached 

 convex articular surface, named the head. 



In the bones of the lower row, it is remarked that the cuboid responds to the fifth and 

 fourth metatarsals; the first cuneiform to the third; the second cuneiform to the second 

 metatarsal : and the third to the first. 



2. Metatarsus. — The metatarsus is composed of five bony columns, nearly parallel to each 



