SKELETON OF QUADRUMANA. 549 



tuberosities beneath the proximal articular surfaces are better 

 developed. The proximal phalanges differ not only in their 

 greatly superior size, but in the deep excavation of their under 

 or anterior surface, which is bounded by rough lateral ridges ; 

 they are also more flattened and rather more bent. The distal 

 phalanges of the anterior extremity are longer, more slender, and 

 less expanded at their rough terminations. 



Each OS innominatum in the adult male Gorilla, 62, is one foot 

 three inches in length, that of Man being seven inches and a half: 

 the breadth of the ilium is eight inches and a half, that of jSIan 

 being six inches. The ilium is less concave, of a more triangular 

 figure, the anterior border being much longer and straighter. The 

 more elongated and narrower form of the sacral surface corresponds 

 with what has been noticed in the sacrum : the posterior angle or 

 spine of the ilium is above that surface, not behind it as in Man : 

 the distance between the antero-superior and antero-inferior spines 

 is much greater in the Gorilla : the antero-inferior spine is situated, 

 as in Man, just above the acetabulum. The upper ischiatic notch 

 is much less deep than in Man, and there is a very feeble rudiment 

 of the tuberosity dividing it from the lower notch. The aceta- 

 bulum is not much larger than that of Man : the posterior is 

 deeper than the upper wall, providing for resistance to the femur 

 in a semi-flexed rather than in an erect position. The ischium 

 extends, as in the Chimpanzee, far below the acetabulum, where 

 it forms a strong subtrihedral column, terminating in a large 

 flattened outwardly bent tuberosity, the aspect of which is wholly 

 downward, not backward, as in INIan : the united plates of the 

 ischium and pubes, bounding the obturator foramen internally, 

 are considerably broader than in INIan. The plane of the ilium is 

 twisted almost at right angles with that of the ischium and pubes. 



The femur, 65, is shorter than in Man, and much shorter in 

 proportion to the breadth of the shaft : the head is more relieved 

 from the neck, and shows a less deep depression for the ligamentum 

 teres ; the neck is less oblique than in Man ; the great trochanter 

 rises to a level with the upper border of the head ; the small tro- 

 chanter is less prominent, but has a larger base than in Man, and 

 is more remote from the great trochanter. The linea aspera is 

 less developed, and the back part of the lower half of the shaft is 

 flat and smooth : tlie inner angle of the popliteal space presents a 

 well-marked rough depression, which is not present in the Human 

 femur, and the shaft more gradually expands to the condyles. 

 The outer articular condyle is narrower than the inner one, the 

 reverse being the case in Man : the inner condyle is not longer 



