CHAP. IL] THE BRAIN. 1059 



the pyramidal tract to the motor fibres of the appropriate nerves, 

 undergoing possibly some change at the place in the cord where 

 the pyramidal fibre makes junction with the fibre of the anterior 

 root, but deriving their chief if not their whole coordination from 

 the cortex itself, that is to say, being coordinated at their very 

 M.irting point. That such a view is untenable, and that the 

 simplicity of the electrical phenomena is misleading is shewn by 

 the following two considerations among others. On the one hand, 

 as was shewn in a previous section, the coordination of movements 

 may be carried out apart from the cortex, namely, in the absence 

 of the hemispheres ; and we can hardly suppose that there should 

 be two quite distinct systems of coordination to carry out the same 

 movement, one employed when volition was the moving cause, and 

 the other when something else led to the movement. On the 

 other hand, the analogy of speech justifies us in concluding that 

 the cortical processes do take advantage of a coordination effected 

 by the action of other parts of the nervous system. 



Bearing this in mind, we may recall attention to the remarkable 

 effects which result from removal of the area. These are twofold. 

 In the first place, there is more or less complete paralysis of the 

 limb ; all the movements of the limb are for a time ineffective. It 

 is not that purely voluntary movements are alone, so to speak, cut 

 out, the reflex and other movements are also impaired or tem- 

 porarily abolished, and as we have already said in many cases at 

 least the sensations of the limb are interfered with. These troubles 

 are of course in part the effects of the mere operative interference 

 belonging to what we spoke of in 582, as being of the nature of 

 shock. But, even giving full weight to this consideration, there 

 remains the fact that the cortical area is associated with the various 

 coordinating and other nervous mechanisms belonging to the limb 

 by such close ties that these are thrown into disorder when it is 

 injured. And side by side with this we may put the remarkable 

 fact previously stated, that during an abnormal condition of the 

 cortical area stimulation of the area, instead of producing the 

 appropriate movements confined to the limb, may give rise to 

 movements of other parts culminating in epileptiform con- 

 vulsions. 



In the second place, this paralysis is temporary only, the 

 voluntary movements are after a while regained, and that in spite 

 of the fore-limb moiety of the pyramidal tract permanently de- 

 generating along its whole length, neither it nor the cortical area 

 ever being regenerated. This shews that whatever be the chain 

 of events in the intact animal, it is possible for the ' will ' of the 

 animal to get at the muscles and motor mechanisms of the fore-limb 

 by some other path than that provided by the appropriate cortical 

 area and corresponding path of the pyramidal tract ; and the facts 

 previously recorded ( 658) shew that that other part is not the 

 corresponding part of the pyramidal system belonging to the other 



