THE LABYRINTHINE SENSATIONS 609 



"he beginning and ending of all movements of the head, or any change in 

 the rate at which it is moving, must cause a momentary alteration of the 

 incidence of pressure of the otoliths on the sensory hairs. Any translatory 

 movements of the head must therefore excite a set of nerve fibres which will 

 be constant for each direction. We are therefore justified in ascribing to 

 these organs the functions possessed by the otolith organ throughout the 

 animal kingdom, viz. the transmission of impulses to the central nervous 

 system which are aroused by the position or movements of the head, and, like 

 the sensations from the muscles, regulate and govern any motor reactiontoji 

 sensory-stimulus. Of these afferent impulses a certain proportion will arrive 

 at the cerebral cortex, and in consciousness will inform us of our position in 



Space anrl nf tViP rh'rpptinn nnrl mrfrmt nf ^ny 7rtnyprpppt ; frptiyp or passive, of 



thread. 



20 



