282 BACTERIAL POISONS. 



nitrogenous bases do result from the decomposition of 

 animal and vegetable proteids (see p. 242). 



The leucoma'ines proper can be divided into two distinct 

 and well-defined groups : (1) the Uric Acid Group, and 

 (2) the Creatinine Group. 



The first of these divisions contains a number of well- 

 known bases which are closely related to uric acid. The 

 order in which they will be described is as follows : 



Adenine, C 5 H 5 N 5 . 



Hypoxanthine, C 8 H 4 N 4 O. 



Guanine, C 5 H,N ft O. 



Xanthine, C 5 H 4 N 4 O 2 . 



(Uric Acid, C 5 H 4 N 4 O 3 .) 



Heteroxanthine, C 6 H 6 N 4 O 2 . 



Paraxanthine, C 7 H 8 N 4 2 . 



Carnine, C 7 H 8 N 4 3 . 



Pseudoxanthine, C 4 H 5 N 4 O. 



Gerontine, C 5 H M N 2 . 



Spermine, C 2 H 5 N (?). 



The members of the second group have all been dis- 

 covered by GAUTIER, and by him are regarded as allied 

 to creatine and creatinine. These two substances, especially 

 the latter, have been hitherto regarded as strongly basic in 

 character, but SALKOWSKI has recently shown that creati- 

 nine, when perfectly pure, possesses little or no alkaline 

 reaction, and, moreover, does not combine with acids. The 

 bases in this group are : 



(Creatinine, C 4 H 7 N S O.) 



(Creatine, C 4 H 9 N 3 O 2 .) 



Cruso-creatinine, C 5 H 8 N 4 O. 

 Xantho-creatinine, C 6 H 10 N 4 O. 



Amphi-creatine, C 9 H K N 7 O 4 . 



Base, C n H 24 N 10 5 - 



Base, C 12 H 25 N U 6 . 



Besides these two general classes of leucoma'ines, there 

 may be made a third class of undetermined leucomaines, 



