82 
PRIMROSE : THE ANATOMY OF THE ORANG OUTANG 
3. Dorsal interossei. 
and in the foot occasionally 
4. Abductor ossis metatarsi minimi digiti. 
Intermediate layer. 
1. Flexor brevis pollicis I 
[superficial head. 
2. Flexor brevis minimi digiti. 
3. Plantar interossei. 
4. Opponens. 
Palmar layer. 
Adductor Pollicis 
[transversus. 
We can now readily establish homologies for the hand and foot, and 
we may construct a table thus : 
Flexor brevis pollicis Flexor brevis hallucis 
{a) Radial head (a) Tibial head 
(i>) Ulnar head (d) Fibular head 
Flexor brevis minimi digiti Flexor brevis minimi digiti 
Abductor pollicis Abductor hallucis 
Abductor minimi digiti Abductor minimi digiti 
Opponens pollicis Opponens hallucis 
Opponens minimi digiti Opponens minimi digiti 
Adductor obliquus pollicis Adductor obliquus hallucis 
Adductor transversus pollicis Adductor transversus hallucis 
Interossei (Palmar and Dorsal) Interossei (Plantar and Dorsal). 
Homologies are thus established for the limb muscles, as has been 
done also for the skeletal parts ; one may add that an attempt is also 
made to establish homologies for the nerves {vide Quain, Vol. III., Pt. 3, p. 
384). I shall not, however, attempt to discuss the homologies of the 
nerves in this paper. Whilst we can thus establish homologies between 
the structural elements pf the hand and foot, we yet observe certain 
anatomical differences due, I consider, to modification from a common 
type of origin. The foot of man is modified as an organ for support, 
whilst the hand of man, in the erect attitude of the individual, is left free 
to minister to his varied needs. There can be little doubt concerning 
the correctness of the view that these two extremities are derived from 
a common type and that the differences observable between the hand 
and the foot are due to modification resulting in departure from the 
