338 THE SPINAL NERVES. 



filaments to the tarso-metatarsal articulations and the periosteum of the metatarsal 

 bones, and terminate in the metatarso-phaiangeal joints. The second and some- 

 times the first of these nerves give twigs also to the dorsal interosseous muscles 

 upon which they lie (Riidinger, Cunningham). 



Varieties. Occasionally the anterior tibial nerve supplies also the inner side of the great 

 toe, or the adjacent sides of the second and third toes. In one case the anterior tibial nerve sent 

 branches to the outer three and a half toes, the great toe and the inner half of the second being- 

 supplied by the musculo-cutaneous (F. T. Roberts. Liverpool Med. and Surg-. Reports, vi. 

 1867). Very rarely the digital branches are altogether wanting. 



SUMMARY OF THE EXTERNAL POPLITEAL NERVE. This nerve supplies, besides 

 articular branches to the knee, ankle, and foot, the muscles and integument of the 

 outer side and front of the leg and dorsum of the foot. It gives the peroneal 

 communicating branch to the short saphenous nerve, and communicates with the 

 long saphenous nerve. 



SYNOPSIS OF THE SENSORY DISTRIBUTION OF THE 

 CEREBRO-SPINAL NERVES. 



1. In the head. The face, and head in front of tlie ear are supplied with 

 sensory nerves from the fifth cranial nerve. The ophthalmic division supplies 

 branches to the forehead, upper eyelid, and dorsum of the nose. The superior 

 maxillary division supplies the greater part of the cheek, the side of the nose, upper 

 lip, lower eyelid, and the region behind the eye over the fore part of the temporal 

 fascia. The inferior maxillary division supplies the chin and lower lip, the hinder 

 part of the cheek, the fore and upper parts of the pinna of the ear on its outer side, 

 and the integument in front of the ear and upwards on the side of the head. 



The head behind the ear is mainly supplied by the great occipital branch of the 

 posterior division of the second spinal nerve, but above the occipital protuberance 

 there is also distributed the branch from the posterior division of the third spinal 

 nerve ; and in front of the area of the great occipital nerve is a space supplied by 

 anterior divisions of spinal nerves, viz., the back of the pinna of the ear, and the 

 lower part of its outer surface, together with the integument behind, and that 

 in front over the parotid gland, which are supplied by the great auricular nerve 

 (2, 3 c) ; while between the area of this nerve and the great occipital the small 

 occipital nerve (2, 3 c) reaches the scalp, and sends a branch to the upper part of 

 the pinna. The auricular branch of the pneumo-gastric nerve also is distributed on 

 the back of the ear. 



Cavities of the head. The mucous membrane of the nasal fossa is supplied by 

 the olfactory nerves and the first and second divisions of the fifth nerve. The 

 ramifications of the olfactory nerves are restricted to the small olfactory region at 

 the highest part of the cavity; the nasal branch of the ophthalmic division of the 

 fifth nerve supplies the anterior portion of the lining membrane; and the superior 

 maxillary serves all the remainder. The frontal sinus is supplied by the nasal nerve, 

 the ethmoidal cells and sphenoidal sinus by the nasal and superior maxillary, and the 

 maxillary antrum by the superior maxillary nerve. 



In the mouth, the upper lip, the teeth of the upper jaw with the gum, and the 

 mucous membrane of the hard palate, are supplied by the superior maxillary nerve. 

 The lower lip and the inner surface of the cheek, the lower teeth and the gum, and 

 the greater part of the tongue in front of the anterior pillars of the fauces, together 

 with the mucous membrane of the alveolo-lingual sulcus, are supplied by the inferior 

 maxillary nerve. The taste-fibres of the fore part of the tongue probably run in the 

 chorda tympani; and the root of the tongue is supplied by the glosso-pharyngeal 



