THE LOWER BRAIN. 



489 



crawls up the board until it gains a new position in which its 

 center of gravity is restored to its proper place. Its movements 

 are exactly those of an entire frog except that they need an 

 external stimulus to call them forth/' It is quite clear that 

 all motor phenomena are carried out, notwithstanding the ab- 

 sence of parts of the brain which have been undeniably shown 

 by experiments in animals, pathological conditions of the 

 human hemispheres, etc., capable of inciting them. The familiar 

 convulsive movements in various parts of the body, trunk, leg, 

 arm, etc., when certain motor areas are stimulated would mean 

 nothing to us if the use of electricity for this purpose were the 

 basis of this doctrine, but lesions in these areas have unquestion- 

 ably proven that they do preside over motor functions, not only 

 in a general way, but in the sense implied by "cerebral localiza- 

 tion." How account for the self-evident discrepancy which the 

 entire absence of these structures indicates in present concep- 

 tions of the processes involved? 



We are brought nearer to a solution when the removal of 

 cerebral tissues those to which we have referred as jarred 

 by the electric current passed by the Weber brothers between 

 the nose and the bulb is continued downward until the cord 

 only is left. "Very marked is the contrast," says Professor 

 Foster, "between the behavior of such a frog which, though 

 deprived of its cerebral hemispheres, still retains the other 

 parts of the brain, and that of a frog which possesses a spinal 

 cord only. The latter when placed on its back makes no at- 

 tempt to regain its normal posture; in fact, it may be said 

 to have completely lost its normal posture, for even when 

 placed on its belly it does not stand with its forefeet erect, as 

 does the other animal, but lies flat on the ground. When 

 thrown into water, instead of swimming it sinks like a lump 

 of lead. . . . When a board on which it is placed is in- 

 clined sufficiently to displace its center of gravity it makes 

 no effort to regain its balance, but falls off the board like a 

 lifeless mass." Such a frog moves its limbs irregularly, but 

 one has but to witness such motions to at once conclude that 

 they are aimless, mere random expressions of the inherent 

 power to contract possessed by all muscular tissues, and which 

 even persist some time after death, especially in the case of 



