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MANUAL OF ELEMENTARY ZOOLOGY 



these series are found in the neck. Among them are the 

 following: (i) The hypoglossal, curving forwards round the 

 angle of the jaw, with a backward branch, known as the 

 ramus descendens, which passes to certain of the neck 

 muscles ; (2) the vagus, running backwards outside the 



%/-- 



FlG. 332. — The brain of a rabbit from below. 



c.ai. t Corpus albicans ; fl., flocculus ; fr.l.-, frontal lobe of the cerebral hemisphere ; 

 kip.l., hippocampal lobe ; m.ob., medulla oblongata ; oi.d., olfactory bulb ; ol.t., 

 olfactory tract ; p. V. , pons Varolii ; pit., pituitary body ; rh./., rhinal fissure ; 

 Sy./., Sylvian fissure ; tp.l., temporal lobe of the cerebral hemisphere ; 1 1. -XII., 

 roots of the cranial nerves. 



carotid artery and giving off a superior laryngeal branch to 

 the larynx, a depressor branch, 1 which arises near the superior 



1 This nerve, which runs to the heart, receives its name on account 

 of its function. It conveys from the heart to the brain afferent im- 

 pulses, as a result of which the central nervous system, acting through 

 other nerves, lowers the pressure of the blood. In the thorax, the 

 main vagus. sends other branches to the heart. 



