584 CHEMISTRY OF THE PROTEIDS CHAP, xn 



another melanin Wolff obtained 1 5 per cent of a hydro-aromatic body, 

 which was identical with xyliton, and which agrees with Spiegler's 



C CH 3 



isotributylen in containing the radical /C = C^ 



C/ X CH 3 



H 2 (CH 3 ) 2 



(CH 3 ) 3 -C / C ~ e v 



;>C = C(CH 3 ) 2 (CH 3 )C/ )C = C(CH 3 ) 2 



(CH 3 ) 3 C 7 C 



isotributylen H O 



xyliton (Kerp and Miiller). 



In addition to xyliton was found isovaleronitril to the extent of 2 '5 

 per cent. Another substance of unknown composition was isolated. 

 How the sulphur is linked on in the melanin could not be determined. 



Brandl and Pfeiffer and Wolff 1 digest melariotic liver with 

 pepsin + HC1, till albumoses can no longer be demonstrated, and then 

 extract the residue with 8 per cent soda-solution. 



The melanins from the hair, the skin, choroid coat of the eye, and 

 the ink-bag of Sepia agree in their properties with the melanins found in 

 tumours. Landolt found indol and ammonia amongst the dissociation- 

 products. 



1 H. Wolff, Hofmeister's Beitrage, 5. 476 (1904). 



