224 MR. E. SCHUNCK ON THE 



carbonic acid are disengaged, while the 2 equivalents of pro- 

 pionic acid as well as the 2 equivalents of acetic acid derived 

 from the other two equivalents of indiglucine unite with the 

 indigo-blue nucleus to produce indiretine. When a indiful- 

 vine is formed it must be assumed that 1 equivalent of indi- 

 glucine after taking up 2 equivalents of water, splits up into 

 3 equivalents of formic acid and a body represented by the 

 formula C 6 H 6 2 , as follows: — 



Cu Hio 13 + 2 H O = 3 C 2 H 2 4 + C 6 H 6 2 . 



Now the last is the formula belonging to the aldehyde of 

 propionic acid and by adding to this formula that of indigo- 

 blue the sum will represent the composition of a indifulvine. 

 The more complicated formula given above for b indifulvine, 

 viz. C44 H 19 N 2 3 represents a compound of 2 equivalents of 

 indigo-blue with a body whose formula is Ci 2 H 12 2 and which 

 is therefore homologous with propylic aldehyde, its origin 

 being due to 2 equivalents of indiglucine being decomposed 

 in such a manner as to give rise to formic acid and carbonic 

 acid in accordance with the following equation : — 



2 C H 10 12 + 2 H = 5 C 2 H 2 4 + 2 C 2 -f C 12 H 12 2 . 



It will be observed in all these cases, with one exception, 

 viz. that of indihumine, that in the assumed combination of 

 the elements of indigo -blue with those of these various acids 

 &c, one or more equivalents of water must be supposed to 

 be eliminated, as will be seen by a glance at the following 

 equations : — 



Indihumine. Indigo-blue. Acetic acid. 



C M H, N0 6 = C 16 H 5 N0 2 + C 4 H 4 4 



Indifuscone. Indigo-blue. Propionic acid. 



H»H 10 NO, = C l6 H 6 N0 2 + C fl H 6 4 — HO 



Indifuscine. Indigo-blue. Propionic acid. 



C M H 10 NO 9 = C 16 H 5 N0 2 + C 6 H 6 4 + 2C0 2 — HO 



a Indifulvine. Indigo- blue. Propylic aldehyde. 



C K H 10 NO 3 = C 16 H 5 N0 2 + C 6 H 6 2 — HO 



