'Vhv Kxcitable Cortex »)!" tin- ( 'liiinpan/A-c. ( )niii^-rtaji, iiii<l (Joiillji 155 

 liuli'X to Primary Movenient^ Listed. 



Niiiiural ..r letur in Hat. Niiniersil or letltr in ll»t. 



Ii|jc I 37, 39 fKS. (11, i»9 rliin lliiK'i-r 16l', 1(J8 ITo 



iio»e (i, K, S, T, V, /. little fliiKiT ... li;;!, 170 



pinna <i( ear 1', P, 1\ tlnKerw without tliiiriii> 171-181,191 



cheek 3,s, no, irj, ii:t IhiKers nml thiiiuli ... 18-.'-lU0, iw'-nn 



chin .'U tliU'i- ulnar lingers I'J.'v'-iOO, 207 



eyetinxv iiuil frontallH I). K whole liiiml 'JO'J-'J(Mi 



tongue a'.', «), f.i; 97. »•.», U.''. ' wrist ' ' Hiw 230 



jaw .... 39,43,45,46.101 109,111.114 elhow '^3 1 2.(7, 260 



hyoid region ii nhouliler 238-260 



(anees 9. » chest wall VI. -IX., 263 



palate ... 98 abilominal wull .\. XVIII.' 2.'>4 



iiviilu . . 100 hallux 2llo'-28.'> 



vocal cords . a, $, y. & 2ii(l toe ... .... •J.S7-288 



larynx aa oli.ser»eil from « ithout .... I. -nd and :tril toea ...... 289 



eyelids, elosins . ah, k. ni, n, i>, <i, t, w three tlhular toes 290, ifWi 



eyelids, opening 380-388 dibits except hallux . JHl-JO!!, :«)l-3aj, ;}<;4 



eyeball 370-379 all digits ,{«)0, .307-309 



neck N, II. -V. ankle .... .... 310-330 



thumb 119-141 j knee ... .... .331-339, 362 



index tinner 142-lliO, 158, 207 hip 340-.'{«l :{ft! 



middle Hntter .... 154, 15.1, 1.^7, lei, lfi2 ' anus .^, .\i..'Aii. 



Biiric'fl Portion of the Motor Cortex. 



It will be .seen from the accompany in<;- charts and the foregoing- H.st 

 that a good deal of the excitable motor cortex lies tucked away from the 

 free surface of the hemisphere, buried in the fissures adjoining gyrus 

 centralis anterior (1!)). We have explored some of tliis buried portion of 

 the motor area by faradi.sation. The unipolar method of .stimulation is 

 suited for such exploring better than is the bipolar ; ])ut the laying bare <^f 

 the deep surface in a tissure necessitates destruction of one wall of it, and 

 haiinovrhage and interference with the minuter local circulation render 

 difficult the successful examination of any large continuous length of a 

 fissure in one and the same specimen. Our results have therefore been 

 obtained piecemeal from a number of hemispheres. Fig. 6, A, B, illustrate 

 the deep points localised in two such experiments ; fig. 6, A is a left hemi- 

 sphere : fig. (), B, a right, the map of which has been reversed for easier 

 comparison witli fig. 6, A, and with other figures. 



The results of our various experiments on this taken altogether revealed 

 no movement from the buried motor cortex which was not elicitable at 

 one time or another in one specimen or another from the free surface of 

 centralis anterior itself. The buried portion in sulcus centralis extended 

 along the whole length of the anterior wall of that fissure except for its 

 extreme upper tip, where motor cortex leaves the fissure and lies a little 

 forward of it. In some places the motor cortex seems to pass down the 

 whole depth of the anterior wall of the fissure, and not far l)elow the inferior 

 genu it seems in .some individuals to occupy the deeper portion of the 

 fi.ssure's posterior wall also. It .seems to extend less deeply than elsewhere 

 into the fi.ssure at two places, one of these being the lower part of genu 

 inferius, the other lower part of genu superius, the shallowing being more 

 marked and sharper at the former. The former of the two corresponds 

 approximately with the region for neck lying between arm area above and 

 face area below. The latter corresponds with the region for abdominal 

 wall and chest wall lying between arm area below and leg area above. 



