204 



C. M. CHILD AND L. H. HYMAN. 



In some cases in these concentrations of ether and alcohol and 

 more frequently in somewhat lower concentrations, the stalk 

 may undergo partial contraction at its apical end before paralysis 

 occurs and in such cases the apical region of the stalk appears as 

 a second region of high susceptibility (Fig. 67). In general, the 

 lower the concentration of alcohol and ether used, the less rapid 



FIGS. 65-67. 



and less complete the paralysis of tentacles and hypostome, the 

 greater the contractile activity of the stalk, and the closer the 

 behavior both in motor activity and in the course of disintegra- 

 tion to the detached animals in cyanide. 



These experiments with alcohol and ether indicate first that 

 inhibition of excitation and the resulting paralysis occur earliest 

 in the tentacles and hypostome region. In concentrations where 

 paralysis does not occur at once it can be seen that the paralysis 

 progresses basipetally in the tentacles. In the column also the 

 paralysis apparently progresses basipetally, although the fact 

 that the body usually contracts before the stalk in the primary 

 excitation may mask this relation in the higher concentrations. 

 Apparently then the susceptibility as regards the paralyzing ac- 



