VIII.] 



THE COMMON FROG. 



121 



This fact has a special interest as bearing on alleged 

 functions of this portion of the brain. 



It has been asserted by some that the cerebellum 

 ministers to the sexual functions ; by others that this 

 part co-ordinates and directs locomotive movements ; 

 and quite lately, that it is related to movements of 

 the eyes. 



3 



Fig. 74.— Brain of Bull Frog in various views. 1, Dorsal view. 2, Lateral view. 

 3, Transverse horizontal section showing the cavities of the olfactory cerebral 

 and optic lobes. 4, Longitudinal section a little to the left of the median line. 

 5, Longitudinal section in median line. The corpus striatum, c, is here exposed 

 to view and also a body, g, within the optic lobes. 5, Longitudinal section in 

 median line. In all five figures :— i, Olfactory nerve ; 2, optic nerve : 4, auditory 

 nerve ; a, olfactory lobe ; b, cerebral lobe ; c, corpus striatum ; d, optic thalamus ; 

 e, pineal gland ; /, pituitary body ; g, optic lobes ; /-;, cerebellum ; i, medulla 

 oblongata. 



The first tv^^o of these hypotheses seem to be com- 

 pletely overthrown by our frog. In the first matter 

 there is anything but a deficiency of energy and 

 activity ; and as to the second, many reptiles are less 

 active and continuous than the frog in their loco- 

 motive efforts. As to the third hypothesis, it should 

 be remembered that the eyes of the frog are large 

 and very moveable, as also that they require a power 



