THE OTIC GANGLION AND ITS CONNECTIONS. 



597 



Fig. 430 shows the distribution of the branches of the trigeminus on the head, and the 

 cervical nerves, so that the distribution of ansesthetic and hyperresthetic areas may easily be 

 made out. 



The otic ganglion (m) lies beneath the foramen ovale on the inner side of the 

 third division. Its roots are (1) short motor fibres from the third division ; (2) 

 vaso-motor from the plexus around the middle meningeal artery (ultimately 

 derived from the cervical ganglion of the sympathetic) ; (3) fibres (A) run from the 

 tympanic branch of the glosso-pharyngeal to the tympanic plexus, and from thence 

 through the canaliculus petrosus in the small superficial petrosal in the cranium, 

 then through a small canal between the apex of the petrous bone and the sphenoid, 



Muse, temporalis. 



Muse, masseter 



N. hypoglossua. 



Platysma myoide -. 

 Muse, sternohyoideus. 



Muse, sternothyreoideus. 

 Muse, omohyoideus. 



Nd. thoracici anteriores 



I fuse, spleiiius. 



Muse, sternocleidomastoideus. 



N. accessorius. 



Muse, levator anguli scapulae. 



Muse, cucullaris or trapezius 

 N. dorsalis scapulae. 



N. axillaris. 



N. thoracicua lsngu*. 



N. phrenicus. ErVa 



Supraclavicular- 

 point. 



Fig. 430. 



Distribution of the sensory nerves on the head as well as the position of the motor points on 

 the neck. SO, area of distribution of the supraorbital nerve; ST, supratrochlear; IT, 

 infratrochlear ; L, lachrymal ; N, ethmoidal ; 10, infraorbital ; B, buccinator ; SM, 

 subcutaneus malte ; A T, auriculo-temporal ; AM, great auricular ; OMj, great occipital ; 

 OMi, lesser occipital ; C 3 , three cervical nerves ; CS, cutaneous branches of the cervical 

 nerves ; C W, region of the central convolutions of the brain ; S C, region of the speech- 

 centre (third left frontal convolution). 



to reach the otic ganglion. Through the chorda tympani the facial nerve is con- 

 stantly connected with the ganglion (fig. 430). 



The branches of the otic ganglion are (1) motor twigs for the tensor tympani 

 and tensor of the soft palate (these fibres are mixed with muscular sensory fibres 

 Jjudwig and Politzer) ; (2) one or more branches connecting the ganglion with the 



