74 
PRIMROSE : THE ANATOMY OF THE ORANG OJJTANG 
TABLE OF THE HOMOLOGOUS BONES OF THE CARPUS AND TARSUS. 
Carpus. 
Typical Names. 
Tarsus. 
Pyramidal . . 
. Ulnare 
. Fibulare . . 1 
[- Os calcis 
Pisiform .... 
. Ulnare sesamoideum(?) . . 
. Fibulare sesamoideum(?) J 
Lunar 
. Intermedium 
.Intermedium 'J 
j. Astragalus 
1 
fRadiale 
. .Tibiale J 
Scaphoid J 
Radiale sesamoideum (?), 
..Tibiale sesamoideum (?l..l 
|- Navicular 
1 
1 Centrale ... 
.Centrale J 
Trapezium. . 
. Carpale i 
. Tarsale i 
. Internal cuneiform 
Trapezoid. . 
. Carpale 2 
.Tarsale 2 
.Middle cuneiform 
Magnum 
. Carpale 3 
. .Tarsale 3 
.External cuneiform 
Unciform . , \ 
f Carpale 4 
..Tarsale 4 
j-Cuboid 
1 
L Carpale 5 
. .Tarsale 5 
Thus it would appear that in the skeleton we have corresponding 
elements to deal with when we compare the hand with the foot. Again 
in connection with the soft parts it is quite obvious that many muscles 
in the foot are represented by corresponding structures in the hand. 
There is, however, room for considerable difference of opinion regarding 
homologies here, and whilst we are unable to go into this subject at 
length in this paper, we may consider it briefly. 
Broadly speaking, the flexor group of muscles in the leg may be 
regarded as homologues of the flexor group in the forearm, and the ex- 
tensors of the leg as homologues of the extensors of the forearm. Hux- 
ley^ suggested, with apparently good reason, that the popliteus of the leg 
arising from the external condyle of the femur corresponded to the prona- 
tor radii teres arising from the internal humeral condyle ; the fact that the 
external femoral condyle is the homologue of the internal humeral con- 
dyle being readily established by tracing the difference in direction of 
the rotation of the limbs in development. We find that pronation and 
supination are movements not possible in the leg, although Bischoff^ 
considers the peroneus longus and brevis to be pronators of the foot by 
raising its outer margin. He is therefore inclined to regard these 
muscles as performing similar functions to the pronators of the forearm 
in their action upon the hand ; similarly he would regard the tibialis 
anticus as a supinator in the foot. These muscles, however (peronei 
and tibialis anticus), have as homologues in the forearm, according to 
Bischoff, the extensor carpi ulnaris and the two radial extensors, but 
these fail to raise the inner or outer margin of the hand as this movement 
is accomplished by pronation and supination of the hand as a whole. 
Bischoff would have us believe that whilst it is possible to establish 
1 Loc. cit., Vol. I, p. 203. 
2 Loc, cit. I, p, 236-7. 
