reissner's fiber in teleosts 225 



experiments during the present (1917) summer, but that has 

 proved to be impossible and must be deferred. 



The fiber was also cut near the posterior end of the cord in a 

 few fishes. In these cases the reactions apparently remained 

 normal. 



It seems to me that the evidence which I have thus far secured 

 points toward the conclusion that Reissner's fiber is ependymal 

 in origin and that it plays no important part in the reactions of 

 the fish. It is necessary, however, to complete all of the pro- 

 posed work, which I hope soon to do, before this question can be 

 answered with complete satisfaction. 



Cambridge, September, 1917. 



