694 MOTOR POINTS IN THE CEREBRUM OF THE DOG. 



Four 



The first primary conv< 



Four ' ' primary convolutions, - in addition, are arranged with reference to these primary fissures 

 volution (I), in the form of a sharply curved knee, embraces the fossa 



Fig. 483. 

 ! < rebrum of the dog from above ; II, from the side ; I, II, III, IV, the four primary con- 

 volutions, S, sulcus cruciatus ; F, Sylvian fossa; v, olfactory lobe ; p, optic nerve; 1, 

 motor area for the muscles of the neck ; 2, extensors and abductors of the fore limb ; 3, 

 lltxors and rotators of the fore limb ; 4, the muscles of the hind limb ; 5, the facial 

 muscles ; 6, lateral switching movements of the tail ; 7, retraction and abduction of the 

 fore limb ; 8, elevation of the shoulder and extension of fore limb (movements as in walk- 

 ing) ; 9, 9, orbicularis palpebrarum, zygomaticus, closure of the eyelids. II, a, a, retrac- 

 tion and elevation of the angle of the mouth ; b, opening of the mouth and movements of 

 the oral centre ; c, c t platysma ; d, opening of the eye ; I, t, thermic centre, according to 

 Eulenburg and Landois. Ill, cerebrum of the rabbit from above ; IV, cerebrum of the 

 pigeon from above ; V, cerebrum of the frog from above ; VI, cerebrum of the carp from 

 above (in all these o is the olfactory lobe ; 1, cerebrum ; 2, optic lobe ; 3, cerebellum ; 

 4, medulla oblongata). 



Sylvii (F). The second convolution (II) runs nearly parallel to the first. The fourth primary 



