Pig- 33 38. Area of Distribution of the Sensory Nerves of the Head. 



These diagrams have been made in accordance with Frohse's investigations and 



ZANDElis data. In fig. // the foramina of exit of the chief branches of the 



Vth Nerve have been indicated by black Dots. 



A characteristic feature of the Cranial Nerves is that they are either pure 

 Motor or pure Sensory nerves ; when they contain fibres of the other variety they 

 do not represent true mixed nerves lil<e the Spinal Nerves. The anterior half 

 of the head is supplied by the Vth Cranial Nerve, the posterior half by the Cervical 

 Nerves, a very small portion only of the Pinna being supplied by the Auricular 

 Branch of the Vagus (cf. the black area in Figs. 35 — 38, and in Fig. 34 the white 

 nerve marked A'). 



The I St division of the Vth Nerve (red) supplies the forehead and vertex 

 of the skull as far back as a vertical line drawn upwards from the posterior border 

 of the Pinna, the middle portion of the upper Eyelid and the Lateral aspect of 

 the Dorsum of the Nose. A branch of the Nasal Nerve supplies the anterior part 

 of the nasal mucous membrane whereas its outer branch only becomes superficia 

 between the Nasal Bone and the Nasal Cartilage (cf. Fig. 50). 



The 2nd Division (3' el low) covers the smallest cutaneous area suppl3dng 

 the teeth of the upper jaw (Superior Dental Nerves), the nasal mucous membrane 

 (Nasopalatine Branches) and through the Infra-orbital Nerve the lower eyelid and 

 the upper lip. 



The 3rd Division (blue) gives off Motor Branches to the muscles of 

 mastication and to the M3'lohyoid Muscle. Its Sensory Branches are the Auriculo- 

 Temporal, Long Buccal and Mental Nerves. 



Cervical Nerves. The Great Auricular plays an important part in the 

 Nerve supply of the Face by supplying the region over the Parotid and the 

 Masseter. 



One of its branches ascends between the Helix and Antihelix. The outer 

 side of the Pinna is accordingly supplied b}- 3 nerves: — Auriculo - Temporal, 

 Auricular Branch of Vagus and Great Auricular. 



The foramina of the 3 branches of the Vth Nerve viz. the Supra-orbital 

 Foramen (notch). Infra-orbital and Mental Foramina lie almost in a vertical line 

 (K. v. Bardeleben). In Neuralgia these points are exceedingly tender. A glance 

 at Figs. 35 to 38 indicates the enormous variations in the cutaneous suppl}\ Thus 

 (cf. Fig. 36) the Infra-orbital Nerve ma}' supply the whole of the middle portion 

 of the Dorsum of the Nose and eliminate the Outer Branch of the Nasal Nerve 

 from the Tip of the Nose. Fig. 38 shew-s a very considerable extension of the 

 Cervical Area. Variations not only occur in different individuals but even in the 

 same individual, so that the cutaneous supply is different in each lateral half of 

 the face. Frequent anastomoses occur so that one area may be supplied by 

 several nerves. Stress should be laid on the fact that the nerves cross the middle 

 line to the opposite side (cf. Fig. 33). 



