THE CREATININ GROUP. 455 



that may be raised as to the chemical individuality or purity of some 

 of these compounds. The study of the hexon bases and of the mon- 

 amino- and di-amino acids in general make such a revision all the 

 more necessary. 



The following method was employed by Gautier in his study of 

 the leucomains of muscle tissue : The finely divided fresh beef-meat 

 or the Liebig's meat extract is treated with twice its weight of water, 

 containing 0.25 gram of oxalic acid, and one to two c.c. of com- 

 mercial peroxid of hydrogen per liter. The purpose of these pre- 

 cautions is to prevent fermentation. Inasmuch as peroxid of hy- 

 drogen is not without action on organic substances its use should 

 be avoided. At the end of twenty-four hours the liquid is raised to 

 the boiling point, then filtered through linen, and the residue is 

 thoroughly squeezed. The filtrate is again raised to the boiling 

 point in order to coagulate any remaining albumin, and finally 

 filtered through paper. The clear liquid thus obtained is evaporated 

 in a vacuum at a temperature not exceeding 50°, and the acid syrupy 

 residue is extracted with 99 per cent, alcohol ; the alcoholic extract 

 is in turn evaporated in a vacuum, and the residue taken up 

 with warm alcohol of the same strength. The filtered alcoholic 

 solution is set aside for twenty-four hours, and any deposit which 

 forms is removed by filtration ; ether (65°) is then added as long as 

 a precipitate continues to form, and the whole is again allowed to 

 stand for twenty-four hours. The ether-alcoholic filtrate from this 

 precipitate is evaporated first on the water-bath, and finally in a 

 vacuum ; the slight residue obtained contains a small quantity of 

 basic substances possessing the odor of hawthorn. 



The syrupy precipitate produced by the ether partially crystallizes 

 on standing ; a little absolute ether is then added, and after standing 

 several days more the liquid is separated by means of an aspirator 

 from the deposit of crystals (A). These are first washed with 99 

 per cent, alcohol, and then extracted with boiling 95 per cent, alcohol. 

 The alcoholic solution, concentrated by evaporation, gives, on cool- 

 ing, a deposit of lemon yellow crystals of xantho-creatinin (B), from 

 the mother liquor of which there separates a crop of new crystals 

 (C). The residue of the crystals (A) left after treatment with the 

 boiling 95 per cent, alcohol is extracted with boiling water, which 

 afterward gives a slight deposit of yellowish white crystals of amphi- 

 creatin (D). The aqueous mother liquor on concentration yields 

 another deposit of orange colored crystals of cruso-creatinin (E). 

 Gautier has, furthermore, separated three other bases from the 

 mother liquors of the crystals obtained as above. Thus, a base 

 which he named pseudoxanthin is stated to have been obtained by 

 evaporating the alcoholic mother liquors of B, D, E (?) in a vacuum, 

 taking up the residue with water, and precipitating the hot solution 

 with copper acetate. The precipitate is decomposed with hydrogen 



