392 



CHORD AT A. 



laryngeal, a peculiar nerve which, on the right side, loops 1 

 round the subclavian artery and, on the left side, passes 

 round the ductus arteriosus. In each case it goes forwards 

 beside the trachea to the larynx. 



The sympathetic can be followed as a ganglionated cord 

 between the vagus and its depressor branch, and the spinal 

 accessory and hypoglossal can also be recognised supplying 

 certain of the neck-muscles. 



. 280.— A Median Longitudinal Section through the Rabbit's Bb 



(Mainly after Marshall.) 

 Middle Commissure. Cerebral Hemisphere. 



Pineal Body. 



rebellum. . .^^^^^^^^^\ / --. ^ 



Corpus 

 Callosum. 



Fourth Ventricle. 



Infundibulum. 



Optic Nerve. 



Foramen of Munro. 



The skeleton of the rabbit can be divided, as in preced- 

 ing types, into axial and peripheral portions. It consists in 

 the adult chiefly of bone and it presents the 

 remarkable feature of epiphyses. An epiphysis 

 is a cap of bone which, up to a certain age, can be detached 

 from the main portion of the bone as it is united to it 

 merely by cartilage. The meaning of these epiphyses will 

 be pointed out later (see page 413). 



Skull. — The skull has mainly persistent sutures. The 

 characters of the teeth have already been noticed. The 

 important mammalian features are the heterodont (incisors. 



