280 PEOCEEDINGS OF THE AMERICAN ACADEMY 



the /?, it does not seem desirable to change names that have become 

 familiar until it is absolutely necessary ; and notwithstanding the work 

 that has been done in the investigation of these acids during the past 

 five years, no direct proof has been given as to the position of the 

 bromine atoms. 



Pkenyldibromlactic Acid. 



On evaporating the filtrate from the a monobromlactic acid to a 

 small volume, a substance crystallized out that melted at about 180° C. 

 After recrystallization several times from water, the melting point rose 

 to 184° C, and it gave on analysis amounts of carbon, hydrogen, and 

 bromine corresponding to those required for a phenyldibromlactic acid. 



The acid is very soluble in water, alcohol, and ether, soluble in 

 chloroform, and slightly soluble in carbonic disulphide and benzol. 



We have not as yet succeeded in obtaining the acid in large enough 

 quantities to study its salts, or to decide which of the several possible 

 formulas correctly represents its structure. 



The analyses gave the following results : — 



1. 0.1854 gr. substance gave 0.2257 gr. CO^ and 0.0440 gr. 11,0. 



2. 0.1989 gr. substance gave 0.2440 gr. CO.^ and 0.0470 gr. H2O. 



3. 0.1605 gr. substance gave 0.1870 gr. AgBr. 



4. 0.1812 gr. substance gave 0.2122 gr. AgBr. 



Found. 



3. 4. 



49.60 49.70 



Action of Bromine on Dibromstyrol. 



The dibromstyrol obtained from the decomposition of the /? phenyl- 

 tribrompropiouic acid was placed under a bell glass, with an excess of 

 bromine. The oil gradually thickened, and after two days had ab- 

 sorbed about its own weight of bromine. It was then placed over 

 quicklime, and after remaining there three or four days was washed 

 thoroughly with watei", and then separated from the water by shak- 

 ing with ether. The so purified oil gave on analyses the following 

 amounts of bromine : — 



1. 0.2050 gr. substance gave 0.3646 gr. AgBr. 



2. 0.2110 gr. substance gave 0.3737 gr. AgBr. 



3. 0.2055 gr. substance gave 0.3651 gr. AgBr. 



