GO COMPARATIVE ANATOMY. 



addition to those already mentioned, viz. the large submaxillary 

 salivary glands bounding the angle of the lower jaw, and the 

 much smaller and more diffuse parotid gland placed behind and 

 beneath the external ear. On the right side of the animal's 

 head and situated at a point just in front of the ear, the extra- 

 orbital factor of the right lachrymal gland can be seen ; from 

 this portion a duct, with a slip of blue paper beneath it, passes 

 forwards to join a second duct from the intra-orbital part which 

 is situated at the posterior angle of the eye and inside the orbit. 

 Near the inner and anterior angle of the eye there is another 

 small gland about the size of a pin's head ; this is the Harderian 

 gland. Of the third eyelid, or membrana nictitans, with which 

 this gland is always correlated, a rudiment exists and can be 

 seen covering the anterior third of the eyeball. 



A black bristle has been placed beneath one or two of the 

 external branches of the seventh or facial nerve, as they cross 

 the largely developed masse ter muscle. 



The characteristic Kodent dentition should be noted : the 

 large, scalpriform, incisor teeth, of which there are two in each 

 jaw, growing from persistent pulps; the absence of canines, and 

 the large interval which separates the incisors from the molars. 



The roof of the skull as well as the neural arches of the 

 cervical vertebrae have been removed in order to expose the brain 

 and spinal cord. The hemispheres are pear-shaped, thin, and 

 tapering in front, but broad behind ; their surfaces are smooth. 

 In the median longitudinal fissure which separates the hemi- 

 spheres, the longitudinal sinus, filled with red injection, can be 

 seen. The olfactory lobes are very large and are altogether 

 uncovered by any anterior extension of the hemispheres. The 

 cerebellum has a large median and two smaller lateral lobes. 

 In the transverse slit between the hemispheres and the cerebel- 

 lum the corpora quadrigemina are partially exposed. The 

 medulla oblongata is wide and passes behind into the spinal 

 cord. 



CA31L1UDGE : naXTED BY C. J. CLAY, M.A. AT THE UN1VEKS1TY PJUESS. 



