Cotnpensatorv Motions 



451 



but the response to every stimulus is the same in degree and in 

 direction. 



Lyon ('99, p. 89) has ah-eady called attention to this anomalous 

 appearance, and the facts had been observed much earlier (Cyon 

 '97, p. 42; Ev^ald '90, Fig. 51; Schafer '87), and had caused great 

 confusion largely because the earlier writers described the re- 

 sponses with reference to the periphery and the axis instead of 



r,Gi 



with relation to the body of the animal. The anomalies and 

 confusions did not lead directly to a rejection of the hypothesis 

 that the semicircular canals were the peripheral organs for per- 

 ceiving acceleration or spatial relations. Yet these theoretical 

 considerations would seem to make the semicircular canal hypothe- 

 sis of equilibration untenable without radical modification. The 

 experimental evidence is conflicting and inconclusive. 



