418 BOTANICAL GAZETTE [NOVEMBER 
the carboxyl groups with alkali yields a series of phyllins, the last oxygen 
free one being aetiophyllin, which carries the Mg group intact, has the composi- 
tion C;:H;,N,Mg, and hypothetically the structural nucleus 
(i Cc 
oe ane 
rg ee 
ae alas 
Acid treatment of the phyllins removes the Mg and yields the porphyrins, 
pitas testi (Cs:H36N 4), the equivalent of aetiophyllin, being the last of 
the se 
ete of chlorophyll with acids attacks another group, no saponifi- 
cation takes place, and a waxlike Mg-free chlorophyll derivative, phaeophytin, 
is obtained. Its solution differs in color from that of chlorophyll, but the 
green returns upon introduction of a metal, such as Zn, Cu, or Mg. Saponi- 
fication of phaeophytin with alkali yields nitrogen-containing acids and a 
nitrogen-free alcohol phytol (C;H;,OH), which may constitute one-third of 
the weight of chlorophyll and varies widely in amount in various chlorophylls. 
Chlorophyll is associated with an enzyme, chlorophyllase, active in alcoholic 
media, which causes an alcoholysis of the pigment and yields the chloro- 
phyllides, the crystalline chlorophyll of the literature, according to the equation 
(C32H;ON,Mg) (COOCOC,) (COOC.H3») + C.H;OH > C,,11,0H-+ 
chlorophyll @ phytol 
(C32H;ON,Mg) (COOCH;) (COOC.H;). 
ethyl chlorophyllid @ 
Plants can be divided into chlorophyllase-rich, such as Heracleum Spondyl- 
tum, and chlorophyll-rich, such as Urtica sp. 
The substance originally named phaeophytin by WILLSTATTER always 
yielded two distinct groups of decomposition products, one olive green 1 
solution, the phytochlorins, the other red, the phytorhodins. Phytochlorin ¢, 
typical of the former series, is a tricarboxylic acid with two free carboxyl 
groups and one bound as a lactam; while phytorhodin g is a tetracarboxylic 
acid, only two or three of the carboxyls being in the free state. They are 
separated by a method based upon their different solubilities in ether and 
hydrochloric acid. Deteraunation of he erga weight of these substances, 
their g I d their ee 
convinced WILLST. kre the tochlori pais | 
and distinct phaeophytins sh and b respectively), and ae pe in turn are 
derived from two distinct chlorophylls (chlorophyll a and 6). These chloro- 
phylls are obtainable in microcrystalline form and differ somewhat in their 
solubilities in various reagents. 
