312 PROCEEDINGS OP THE AMERICAN ACADEMY 



The above explanation becomes the more probable, because the ad- 

 dition of acetoacetic ether in the form of the sodium salt to define 

 derivatives has already been accomplished in many cases by Michael,* 

 Auwers,t and others. 



The work of which an account is given in this paper has been car- 

 ried out under the direction of Prof. J. U. Nef, to whom I wish here 

 to express my sincere thanks. 



* J. prakt. Chem. (2), XXXV. 349, 449; Michael and Freer, Ibid., XLIII. 90. 

 t Ber. d. chem. Ges., XXIV. 307. 



Worcester, Mass., September, 1891. 



