The hydrolysis was performed by the method of Sadikow and Zelinsky slightly modifying the conditions. 1 kg. of human hair was heated with 8 times its weight of 1 per cent HCl in an autoclave for 6 hours at 180°. The resulting products were successively extracted with organic solvents, such as ether, acetic ether, chloroform, methyl alcohol, ethyl alcohol and butyl alcohol. From the extracts several crystals were isolated in which valyl-leucin anhydride, alanyl-leucin anhydride and glycyl-leucin were identified by the investigation of their character, by the analysis of the crystals, and by the hydrolysis of them into corresponding amino acids.