268 PROCEEDINGS OF THE AMERICAN ACADEMY 



be recrystallized from boiling water without decomposition. The dry 

 salt is decomposed suddenly by heat, but without detoualioii. 



I. 0.3922 grm. of the salt dried over II,SO^ gave on precipitation 

 with II Br 0.2928 grm. AgBr. 

 II. 0.2903 grm. of the salt dried over H^SO^ gave on precipitation 

 with HBr 0.2168 grm. AgBr. 



Ag 



The relation which mucophenoxybromic acid bears to luucobromic 

 is sufficiently shown by its conversion into phenoxybromacrylic and 

 phenoxybrommaleic acids under conditions identical with those neces- 

 sary to the formation of dibromacrylic and dibrommaleic acids from 

 niucobromic. Furthermore, it is evident that the extreme stability of 

 the phenoxybromacrylic acid in alkaline solution shows that the 

 phenoxyl group has taken the place of the bromine atom which is so 

 readily removed from the corresponding dibromacrylic acid in the 

 formation of brompropiolic acid. 



If mucobromic acid be written, 



Clio 



I 



CBr 



II 



CBr 



I 



coon 



it follows that mucophenoxybromic acid has the form, — 



CHO 



I 



CBr 



II 



C-O.C,H, 



I 



COO II 

 and the acrylic acid derived from it has the form, — 



CHBr 



II 



C - O.C.H, 



I 



COOII. 



