334 NERVES OF THE SUBM AXILLARY GLAND. [BOOK n. 



it, as at n.l', Fig. 76, stimulation of the (front part of) tongue pro- 

 duces, under ordinary circumstances, no flow. This shews that 

 the centre of the reflex action is higher up than the point of sec- 

 tion ; it lies in fact in the brain. 



ch.tr 



FIG. 76. DIAGRAMMATIC REPRESENTATION OF THE SUBMAXILLARY GLAND OF 

 THE DOG WITH ITS NERVES AND BLOOD VESSELS. 



(The dissection has been made on an animal lying on its back, but since all the 

 parts shewn in the figure cannot be seen from any one point of view, the figure does 

 not give the exact anatomical relations of the several structures. ) 



sm.qld. The snbmaxillary gland, into the duct (sm.d) of which a cannula has 

 been tied. The sublingual gland and duct are not shewn, n.l, ni. The lingual 

 branch of the fifth nerve, the part n.l. is going to the tongue, ch.t., ch.t'., ch.t". 

 The chorda tympani. The part ch.t". is proceeding from the facial nerve ; at ch.t'. 

 it becomes conjoined with the lingual n.l'. and afterwards diverging passes as cltt.t. 

 to the gland along the duct ; the continuation of the nerve in company with the 

 lingual n.l. is not shewn, sm.ql. The snbmaxillary ganglion with its several roots. 

 a.rar. The carotid artery, two small branches of which, <i sm.a. and r.sm.p.. pass to 

 the anterior and posterior parts of the gland, v.s.m. The anterior and posterior 

 veins from the gland, falling into v.j. the jugular vein, v.sym. The conjoined 

 vagus and sympathetic trunks, ql.cer.s. The upper cervical ganglion, two branches 

 of which forming a plexus (a.f.} over the facial artery, are distributed (n.sym.sm.) 

 along the two glandular arteries to the anterior and posterior portions of the gland. 



The arrows indicate the direction taken by the nervous impulses during reflex 

 stimulation of the gland. They ascend to the" brain by the lingual and descend by 

 the chorda tympani. 



In the angle between the lingual and the chorda, where the latter 

 leaves the former to pass to the gland, lies the small snbmaxillary gan- 

 glion (represented diagrammatically in Pig. 76 sm.gl.). This consists 

 of small masses of nerve cells lying on the small bundles of nerve-fibres 

 which spread out like a fan from the lingual and chorda tympani 



