262 THE BRAIN OF QUADRUPEDS AND 



Where the Pons is well developed, the ' cerebral pedun- 

 cles,' being more covered, appear to be curtailed in 

 length (fig. 74, i, i). 



The Cerebellum in Marsupials (fig. 68), still consists 

 principally of the ' median lobe,' the surface of which is 

 marked by deep transverse fissures, giving rise to a series 

 of nearly parallel convolutions. Its * lateral lobes ' exist 



FIG. 74. Brain of Dolphin, under surface. (Owen, after Tiedemann.) a, Spinal 

 cord ; b, anterior pyramids ; c, Pons Varolii ; e, posterior inferior lobe of Cerebellum ; 

 f, anterior inferior lobe, g, amygdaloid lobe, and h, flocculus, all lobes of Cerebellum. 

 i, i, Cerebral peduncles ; p, corpus albicans ; o, pituitary body ; m, temporal lobe, 

 and I, anterior lobe of Cerebrum. Olfactory bulbs absent ; 2. optic nerves ; 3, motor 

 nerves of eyes (fourth nerve appears from above the Cerebellum, in front of g] ; 

 5, the trigeminus ; 6, the sixth nerve ; 7, the facial, and 8, the auditory nerves ; 

 9, glosso-pharyngeal ; 10, vagus ; 11, spinal accessory; 12, hypoglossal; 13, first cervical 

 nerve. 



merely as small appendages, and are thought by some 

 anatomists to correspond in higher forms with certain 

 accessory lobules, named ' flocculi.' Among Rodentia the 

 lateral lobes show a marked increase in size, which is 

 obvious in the Hare (fig. 76), and still more so in the 

 Beaver (fig. 71) where these parts are distinctly larger 



