1921] SCHERTZ—MOTTLING 115 
found to have about five times as much phytochlorine as the 
Coleus leaves (based on the wet weight). The same relation was 
found to hold for phytorhodin g. This means that the two leaves 
bear a and 6 chlorophyll in the same proportions, but that the lilac 
has about five times as much of each as the green Coleus. Assuming 
that the lilac leaves contain o.8 per cent (the average percentage 
for green leaves) of chlorophyll, then Coleus leaves contain only 
0.16 per cent of chlorophyll, based on the dry weight of the leaves. 
Table XXVIII, quoted from WiILtstATTER, shows the relation 
between autumnal yellowing, chlorophyll content, and photosyn- 
thetic activity. These changes agree generally with the writer’s 
results in the mottling of Coleus in mid-season. 
TABLE XXVIII 
CHANGES AS LEAVES YELLOW IN AUTUMN (LEAVES ALL OF .SAME SPECIES) 
ight | Chlorophyll | CO, assimilated 
Leaf Date aes Horm g roan ioe hour 
Deen gee 5 ceeds i: July 30 yes 19.7 9.080 
ive Cotes inet unax tee GF ge ao cat t.55 1268 Soe ead cays 
Green with yellow spots. . October 5 1.45 7.8 .064 
Almost yellow............. October 10 ‘35 2.1 0.010 
In alfalfa hay JacoBson (23) has shown that 0.68 per cent of 
chlorophyll and 0.28 per cent of yellow coloring matter were 
present. The chlorophyll was estimated after the method of 
MARCHLEWSKI, and was shown to contain 66 per cent neochloro- 
phyll and 34 per cent allochlorophyll. He believed that this ratio 
would vary, depending upon the conditions of growth. 
XANTHOPHYLL.—The xanthophyll in the leaves was estimated 
by comparing the extracted pigment with a standard solution of 
potassium dichromate, as recommended by JORGENSEN and STILES 
(26). There was found to be present in 1000 gm. of fresh lilac 
leaves 0.273 gm. of xanthophyll, in the green Coleus leaves 0.087 
gm., and in the mottled Coleus leaves 0.239 gm. From this it is 
seen that green Coleus has about one-third as much xanthophyll 
as lilac, while fully mottled Coleus has nearly as much as lilac. 
The amount of xanthophyll present in lilac was about the same 
as that present in Sambucus nigra (0.250). The amount of 
