12 PROFESSOR OWEN ON THE OSTEOLOGY OF 
minent lateral ridges, bounding and deepening the groove for the flexor tendons: the 
massive quadrate proportions of these bones are also very striking. The same characters 
are shown, in a minor degree, by the second phalanges, with greater predominance of the 
transverse over the antero-posterior diameter: the third phalanges are chiefly charac- 
terized by their more slender tapering shaft, and their more tuberous and less flattened 
terminations, than in Man. 
In the Gorilia the hand is an instrument for great power of grasp, and for sustaining 
on the metacarpals of the fore fingers great weight: the length and strength of the 
whole pectoral limb accord with these mechanical powers and requirements. In Man the 
framework of the hand bespeaks an organ of varied and delicate prehension ; and the 
form and proportions of the whole upper limb relate to the free motions and complex 
functions of the instrument. 
The bones of the hand in the Chimpanzee agree in most particulars with those ot 
the Gorilla ; but they depart further from the Human type and approach nearer to that 
of lower Quadrumana in the shorter thumb, and in the greater length, in proportion 
to the breadth, of the whole hand. 
Bones or THE Lower Limes. 
Os innominatum.—Plate VI. 
The ilium being the homotype or correlative of the scapula, the ischium of the 
coracoid, and the pubis of the clavicle, | commence therewith the description and 
comparison of the bones of the lower limb. In the upper limb the coracoid becomes 
confluent with the scapula, the clavicle remaining free; but in the lower limb the 
ilium, ischium, and pubis coalesce with each other, forming that single composite bone 
which in Anthropotomy is specified as the ‘ os innominatum.’ 
The iliac portion of the bone shows in the Human species alone that degree of 
expansion and forward inflexion of its upper and anterior border occasioning the 
form that suggested the term ‘ pelvis’ or basin for the segment of the skeleton com- 
posed of the ossa innominata and sacrum (Pl. XII. fig. 1). Every ape, until the Gorilla 
became known to the anatomist, had presented an iliac bone, not only long and narrow, 
but flat, or, if hollow, with the concavity directed backwards instead of forwards. Such 
is the strictly quadrumanous condition of the bone in the common Chimpanzee (Tro- 
glodytes mger, Pl. VI. fig. 3), as well as in the Orang-utans and Gibbons. In the 
Gorilla the iliac bone (ib. fig. 1, a, b, ¢ d), besides showing a greater relative breadth 
in proportion to its length than in the Chimpanzee, has the upper and outer border 
a little bent forward (Pl. XII. fig. 2), giving a moderate concavity or pelvic character 
to that part of the skeleton; it is, however, much inferior in degree to the Human 
pelvis. 
The difference of size between the os innominatum of the Gorilla and that of Man 
is enormous: this part of the great ape’s frame would fit a human giant of ten feet in 
height. But, besides size, there are well-marked differences in form and proportion, 
