642 THE NERVOUS SYSTEM. 
of the zygomatic arch, and is concealed by the ramus of the lower jaw, and by the 
temporal, masseter, and external pterygoid muscles. 
The branches of the inferior maxillary nerve may be divided into two series 
(1) those derived from the undivided nerve, and (2) those derived from the terminal 
divisions of the nerve. 
The branches 
of the undivided nerve are two in number. (a) A small 
recurrent branch (1. spinosus) arises just outside the skull, and accompanying the 
nuddle meningeal artery 
through the foramen 
spinosuin, supplies the dura 
mater. (0) In the pterygoid 
region a small branch 
arises for the supply of the 
internal pterygoid muscle. 
This nerve forms a econ- 
nexion. with. the». ope 
vanghon. 
The terminal divisions 
of the nerve are a small 
anterior and a large pos- 
terior trunk. 
The small anterior 
trunk passes downwards 
and forwards beneath the 
external pterygoid muscle, 
and separates into the fol- 
lowing branches:—(1) A 
branch for the external 
pterygoid muscle (n. ptery- 
goideus externus), which 
Se it on its deep sur- 
face; (2) a branch to the 
masseter muscle (n. mas- 
setericus ), which passes over 
the upper border of the 
external pterygoid and 
DISTRIBUTION OF INFERIOR 
NERVE. 
5, Afferent, and Mo, Efferent roots; M. 
Meningeal branch ; 0.G, Otic ganglion ; I.Pt, Nerve to internal ptery- 
Fic. 462.—ScHEME OF THE 
MAXILLARY 
THE 
V.I.M, Inferior maxillary nerve ; 
goid ; 8.S.P, Small superficial petrosal nerve ; T.T, Nerves to tensor 
tympani, and T.P, Tensor palati ; Ty.Plex, Tympanic plexus ; I.C, 
Internal carotid artery ; §.D.P, Small deep petrosal nerve ; G.G, 
Geniculate ganglion ; F, Facial nerve ; Ty, Tympanic branch; G.Ph, 
Glossopharyngeal nerve; M.M, Middle meningeal artery ; A.T, 
Auriculo-temporal nerve ; F, Communication with facial nerve ; Par, 
Nerve to parotid gland ; Me, Branch to meatus of ear ; Pi, Branch 
to pinna ; T, Temporal branch; A, Anterior division of inferior 
maxillary nerve ; E.Pt, Nerves to external pterygoid ; M, Masseter ; 
T.T.T, Temporal, and Buce, Buccinator muscles; Po, Posterior 
division of inferior maxillary nerve ; L, Lingual nerve ; C.T, Chorda 
tympani nerve ; Sub.G, Sub-maxillary ganglion; Hy, Hypoglossal 
nerve ; I.D, Inferior dental nerve ; My.hy, Mylohyoid nerve ; My, 
Nerve to mylohyoid ; Di, Nerve to digastric (anterior belly) ; Ment, 
Mental branch ; Sty.Gl, Stylo-glossus ; H.Gl, Hyo-glossus ; G.H.G, 
Genio-liyoglossus muscles, 
through the sigmoid notch 
of the lower jaw; (3) and 
(4) two branches to the 
temporal muscle (nn. tem- 
porales profundi, anterior 
et posterior), which also 
ascend above the external 
pterygoid muscle; and (5) 
the buccal nerve (n. bucci- 
natorius), Which passes ob- 
liquely forwards between 
the two heads of the ex- 
ternal pterygoid to reach 
the buccinator muscle. This nerve is sensory, and its fibres are in part distributed 
to the skin of the cheek (communicating with buccal branches of the facial nerve) ; 
they are also in part distributed to the mucous membrane of the inside of the 
mouth, to reach which they pierce the fibres of the buccinator muscle. The 
buccal nerve usually supplies a third branch to the temporal muscle, after emerging 
between the two heads of the external pterygoid muscle (Fig. 458, p. 637). 
The large posterior trunk extends downwards a short way beneath the 
external pter rygoid muscle. After giving off by two roots the auriculo- temporal 
nerve, it ends. by dividing into two, the lingual and the inferior dental nerves. 
The auriculo- -temporal nerve (n. a uriculo- temporalis) is formed by the union 
