256 



Mention the Chief Nerves of the Neck, and indicate their 

 Distribution. 



The tenth cranial nerve, the vagus or pneumogastric, 

 which passes along the outer side of the carotid artery, 

 gives off anterior laryngeal, depressor (to heart), posterior 

 or recurrent laryngeal, and branches to heart, lungs, and 

 oesophagus. 



The eleventh cranial nerve, the spinal accessory, supplies 

 the sterno-mastoid and other muscles. 



The twelfth cranial nerve, the hypoglossal, supplies -the 

 muscles of the tongue. 



The phrenic, a branch of spinal nerve IV., which passes 

 external to the vagus, supplies the diaphragm. 



The ganglionated cervical nerve of the sympathetic 

 nervous system, lying alongside the trachea, between the 

 vagus and depressor nerves. 



Name the Important Structures, other than Nerves, which are 

 situated in the Neck. 



The trachea ; its anterior part, the larynx, surrounded by 

 large thyroid and ring-like cricoid cartilages. 



The thyroid gland. 



The oesophagus. 



The external jugular vein. 



The carotid artery. 



Give a General Description of the Structure of the Eye, Nose, 

 and Ear. 



The eye is without a pecten. See description, page 203. 

 For a description of the olfactory organ, see page 205. The 

 ear has a large, coiled cochlea. See description, page 206. 



Describe the Heart and Principal Blood-vessels of the Rabbit, 

 and indicate the general Course of the Circulation. 



The heart, within a two-layered pericardium, is situated 

 in the middle of the thorax, in that space called the medi- 

 astinum between the pleural sacs. The three venae cavae, 

 which convey the impure blood from the body, open 

 separately into the right auricle ; thence the blood passes 

 into the right ventricle, which partly surrounds the left 

 ventricle but does not quite roach the apex. The right 

 auriculo- ventricular opening is guarded by a membranous 

 tricuspid valve ; its throe lobes are attached by chordae 

 tendineae to papillary muscles of the ventricle wall, and 



