REFLEX ACTIONS. 161 



the plantar reflex, which consists in a flexion of the toes when the 

 sole of the foot is stimulated by tactile or painful stimuli. Under 

 pathological conditions which involve a lesion of the pyramidal 

 tracts in the cord this reflex is altered, the great toe being 

 extended instead of flexed (Babinski's phenomenon). The 

 cremasteric reflex consists in a contraction of the cremasteric 

 muscle which raises the testis. It follows from stimulation of 

 the skin on the inner side of the thigh at the level of the scrotum. 

 The location of the motor centers of these and other similar 

 reflexes is shown in the accompanying illustration (Fig. 72). 



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