EXAMINATION OF SOME SPINAE NERVES 53 
nerve-pair. Then are appended any discrepancies between the results in the short series of 
individual experiments. To assist survey of the whole field of distribution of each entire spinal 
nerve — a survey of mucli importance for the understanding of the physiological anatomy of the 
animal — I have added to the description of the sensorial skin-field a concise account of the motor 
muscular field, determined in special experiments of my own. In tlie brachial and cervical region 
the muscular innervation in terms of spinal nerves is in the Monkey known only through the 
brief report by Ferrier and Yeo,* and the later and less perfect results by Forgue and 
LANNEGRACE.t 
Field of the Fifth Cranial Nerve {N. trigeminus). Fig. 2, p. 59 ; and figs. 4 and 5, 
pp. 64, 65, and sketch furnished to Dr. Head's paper, 'Brain,' loc. cit.^ 1894. 
Anterior Border 
The anterior border is coterminous with the anterior pole of the body. 
Posterior Border 
The posterior border has been delimited in six indiv'iduals. 
Experiment. Macacm rhesus. ?, young. 
Measurements : — 
Infra-pubic notch to umbilicus = 1 1 ccntims. 
Supra-pubic notch to umbilicus = 8 centims. 
Supra-sternal notch to umbilicus = 12 centims. 
Infra-sternal notch to umbilicus = 7 centims. 
The 1st, Ilnd, and Ilird cervical nerves severed in the vertebral canal outside the dura 
mater. 
The posterior edge ot tlie upper field of response was several times delimited and yielded 
the following boundary. 
' The boundary starts from the mid-dorsal line on the scalp at about the junction of 
the posterior with the middle third of the distance from the glabella to the external occipital 
protuberance. Thence it takes an almost rectilinear course to the base of the pinna, about 4 
millims. behind the anterior surface of that structure ; the boundary then ascends the hinder 
(mesial) surface of the pinna, finally attaining to and winding over its upper edge. On the 
anterior (lateral) surface of the pinna,J the boundary descends a little in front of the fossa of tiie 
helix, sweeps forward below the concha to the tragus, and then dips over it slightly into the 
concha, and winds out again in the notch between tragus and anti-tragus. (The auricle of Rhesus 
possesses scarcely any lobule.) Having thus left the ear, the boundary line proceeds along the 
outer face of the vertical ramus of the lower jaw, running slightly in front of the posterior edge of 
it. It crosses just in front of the angle of the jaw, and turns horizontally inward, toward the mid- 
ventral line of the neck, which it reaches a few millims. above the thyroid cartilage.' 
* ' Pioc. Roy. Soc.,' Lonilon, loc. at., 1881. t ' Compt. Rendus Acad. d. Sc.,' Paris, 1884. 
J See Remarks, p. 57. 
