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DR, C. E. BEEVOR AND PROFESSOR Y. HORSLEY ON A 
important of the limb. The remarkable way in which this movement is represented 
in a nearly horizontal line on the cortex must not be overlooked. 
Finally, fig. 8 illustrates most clearly how the mode of march is in harmony 
with the representation of primary movements in the various points in the area. Thus 
the movements consequential to the first movement obey the law we have already 
dwelt upon, viz., that the joints are represented from above down in the area, in the 
order of shoulder, elbow, wrist, digits, and thumb. The truth of this statement is 
rendered very evident when fig. 7 is compared with fig, 8. 
To summarise briefly the facts contained in the foregoing pages, we consider:— 
1. That sulcus x (Schafer) corresponds to the superior frontal sulcus of Man. 
2. That the muscles of the upper limb are progressively represented from above 
downwards, in the outer or convex surface of the hemisphere, in the order of their 
size and the movements of the joints : in the order of shoulder, elbow, wrist, finger, 
thumb. 
3. That the joints are moved in the order of shoulder, elbow, wrist, and hand 
when the highest part of the area is stimulated, and in the converse order—thumb, 
fingers, wrist, elbow, shoulder—when the lowest part is excited, whilst between these 
extreme points the sequence of movement is commenced by a middle joint, i.e., the 
elbow (incompletely), in the ascending parietal convolution, and the wrist to a very 
large extent in the ascending frontal. 
4. That with regard to the quality of movements of the different joints repre¬ 
sented in the cortex, the shoulder presents the following sequence from above down : 
advancing, abduction, rotation out, adduction; the elbow: extension, confusion, flexion; 
the wrist: extension, flexion, and pronation, confusion, supination. In the fingers and 
thumb the sequence is altered, and we have, broadly, extension anteriorly and flexion 
posteriorly. (For details refer to diagrams.) 
5. That there is no absolute line of demarcation between the area of localisation in 
the cortex of one movement and that of another; each movement having a centre of 
maximum representation, this gradually shading off into the surrounding cortex. 
