MOTOR FUNCTIONS OF CEREBRAL CORTEX OF CAT 185 



ber and these were obtained only from the middle third of the 

 field. Movements of the fore limb, which were numerous, fol- 

 lowed stimulations within a field almost co-extensive with the 

 field for hind limb movements. Movements of the head and 

 neck were from stimulations of a field lying almost entirely in 

 front of the crucial sulcus and at the outer part of the motor 

 field. 



Cat 9, right hemisphere. The motor field extended as a 

 whole over an area similar to that of cat 8, and in addition reached 

 the median line. The central portion of the field, lying posterior 

 to the sulcus cruciatus, gave upon stimulation almost exclu- 

 sively movements of the hind limb. Movements of the trunk 

 and tail were initiated by stimulation of two small areas close 

 to the median line. The larger of these areas is at the posterior 

 portion of the motor field and the other on the posterior bank 

 of the crucial sulcus. All movements of the fore limb were ob- 

 tained from stimulation of a large area in front of the crucial 

 sulcus. Movements of the head and neck were obtained from 

 stimulation of two areas, a small area at the anterior portion of 

 the motor field, near to the median line, and a large area poste- 

 rior to the outer end of the crucial sulcus. 



Cat 10, both hemispheres. The right hemisphere presented 

 two distinct fields, one extending about 0.5 cm. in each direction 

 from the sulcus cruciatus and to the median line. This gave 

 upon stimulation only movements of the hind limb, except within 

 a small area anterior to the outer end of the sulcus, which gave 

 movements of the fore limb, trunk and tail. Movements of the 

 head and neck were initiated by stimulation of a small field, ex- 

 tending from the upper end of the fissura rhinalis, almost to the 

 median line. The left hemisphere of this animal presented an 

 arrangement quite similar, except that the area for the hind 

 limb extended further posteriorly. 



Cat 11, left hemisphere. The total motor field extended from 

 the middle third of the coronal fissure to the median line and 

 from a line about 0.5 cm. above the upper end of the olfactory 

 lobe to the anterior extremity of the fissura lateralis. Move- 

 ments of the hind limb followed stimulation within an area ex- 



