EXAMINATION OF SOME SPINAL NERVES 
103 
In my experiments, the field of assthesia persisting upon the fibular edge of the foot 
and extending to the end of the 5th digit, has each time been distinctly separable into a smaller 
part on the digit, and a larger on the lateral edge of the metatarsus. 
The distribution is more clearly understood by reference to the figures 9 (in text) and 10 
than by verbal description. It must be remembered, in comparing them with Man, that, as I 
have pointed out,* there is a communication between external plantar and external saphenous 
The limit of me- 
dian nerve in 
Macacus rhesus 
and sink us. 
Limit of ulnar. 
The limit of me- 
dian nerve in — y 
Cercocebus and 
Cyfiocephalus. 
Limit of median 
nerve. 
of regular occurrence in Macacus, of which I find no record, even as an exceptional variety, in 
Man. The strip of overlap of the skin-fields of the external and internal plantar nerves is seen 
to be distinctly smaller than the overlap of skin between the Vlth post-thoracic and the Vllth 
and Vth post-thoracic nerve-roots, indeed trifling as compared with that. In position it does not 
lie in such a way as to suggest any commensuration at all between the two systems of overlap. 
In the hand of Macacus the mutual overlap of the ulnar and median were examined after 
section of the musculo-cutaneous and musculo-spiral and internal cutaneous trunks in the upper 
* 'Journ. of Physiol.,' vol. 13, 1892. It is not generally recognized that in the Monkey (Macacus), as I showed in my 
' Lumbo-sacral Plexus,' the external saphenous nerve gives motor fibres to the short muscles of the foot, producing, when excited, 
interosseous flexion qf all the digits. 
