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pigments. He published three papers (Sitzber. k, Akad. d. Wiss, 

 Vienna, 1906, 975 ', 1909, 1033 ; and 191 1, 765), in the first of which 

 he described experiments with red cabbage leaves, and rose 

 petals, from neither of which could he obtain any crystalline pig- 

 ment, the blue-black berries of ligustrum vulgare, from which he 

 obtained a crystalline product, but was unable to obtain any 

 agreement in his analyses of it, and finally, with the flowers of 

 the hollyhock (althaea rosea), from which he obtained two pig- 

 ments, one crystalline, one amorphous, and of which he gave 

 analyses. In each case he used the lead compound for the pre- 

 paration of his pigment, and decomposed it by means of sulphu- 

 retted hydrogen. After separation of the hollyhock pigment in 

 this manner, he further purified it by solution in alcohol and pre- 

 cipitation of the pigment by addition of ether ; by further solution 

 of the pigment in alcohol and evaporation of the solvent, the 

 pigment separated in deep red crystalline leaflets. A portion of 

 his product from decomposition of the lead salt by sulphuretted 

 hydrogen was insoluble in alcohol, but soluble in water, and from 

 this he obtained the amorphous pigment which he described. He 

 gave the crystalline compound the formula C 14 H 16 6 , the amor- 

 phous product C 2 oH3 13 , and considered the latter to be a 

 glucoside of a dibasic acid which contained hydroxyl groups, and 

 probably also an aldehyde group. From the amorphous product 

 he obtained glucose by hydrolysis, but apparently did not 

 examine the non-glucoside pigment produced by this reaction. 

 In his second paper he continued his investigation of the holly- 

 hock pigment, and discussed the formation of the anthocyans in 

 the plant. The third paper of the series contains an account of 

 his further attempts to prepare the pigment of the red cabbage 

 in a crystalline form. Despite the fact that Molisch had failed 

 to obtain crystals by his method, Grafe attempted to produce 

 them by using that process on a larger scale. Failing in his 

 attempts, he tried dialysis— previously used in other cases by 

 Portheim and Scholl (Ber. deut. Bot. Ges. 1908, 26a, 480)— as a 

 means of purification, but again failed to obtain any crystalline 

 product. Grafe then turned his attention to the pigment of the 

 scarlet pelargonium, which had so readily yielded Molisch 

 crystals. He was successful in obtaining this pigment in a fine 

 crystalline condition (microphotographs of the crystals were 

 given) by carrying out Molisch's experiment on a large scale, by 

 use of the lead salt method, or by dialysis. Beyond the crystal- 



