320 Mr. E. Schunck and Dr. L. Marchlewski. [Feb. 14, 



These numbers correspond in 100 parts to 



The formulas CsgB^NiOz and C 3 2H32N"40 2 Zn require respectively 



Phylloporphyrin. Zinc salt. 

 C ........ 75-89 67-46 



H ........ 6-73 5-63 



N ........ 11-06 



O ........ 6-32 



Want of substance prevented our making further determinations 

 in confirmation of those above given. 



It is difficult at present to explain in a simple manner the formation 

 of phylloporphyrin from phyllotaonin, the more so since phyllopor- 

 phyrin is not the only product of decomposition due to the action of 

 alkali, it being always accompanied by a relatively large quantity of 

 brown amorphous substances as before mentioned. Ammonia, 

 together with a small quantity of another base having a higher 

 molecular weight, could also be detected in the acid liquid filtered off 

 from the phylloporphyrin and the brown substances, just as in the 

 case of alkachlorophyll ; the presence of these bodies was discovered 

 in the manner previously described. 



Conversion of Phylloxanthin into Phyllocyanin. 



Phylloxanthin and phyllocyanin being both products of decomposi- 

 tion of chlorophyll with acids, and having many properties in common, 

 it seemed probable that a connection of an intimate character might 

 be found to subsist between the two substances. Our experiments lead 

 to the conclusion that this is, in fact, the case, and that phylloxanthin 

 may by the prolonged action of acids be converted into phyllocyanin. 

 This convertibility has frequently been suspected, but has never yet 

 been satisfactorily proved. 



The changes which take place in the spectrum of chlorophyll on 

 the addition of acids to its solutions have long been known, they have 

 been accurately described by Russell and Lapraik in their memoir 

 entitled "A Spectroscopic Study of Chlorophyll." * 



According to these observers, when a few drops of hydrochloric 

 acid are added to an ethereal solution of chlorophyll, the colour of the 

 latter changes from bright green to yellowish-green. At the same 

 time the spectrum of the solution undergoes a marked change : bands 



* ' Chem. Soc. Trans.,' vol. 41, p. 334, 1882. 



