1921] SCHERTZ—MOTTLING 99 
Phosphates were determined by the NEuMANN-PEMBERTON 
(35) method and the result is given as free phosphorus. In each 
analysis 20 gm. of fresh leaves was used, and before being analyzed 
was dried at 100° C. in order to determine the dry weight. 
The amount of phosphorus present in mottled Coleus leaves 
was considerably less than in green ones, and the phosphorus 
content of the green leaves was about the same as that of other 
leaves (tobacco and beech), but the phosphorus content of pea and 
bean leaves was higher than that of green Coleus leaves. As 
calculated from table VII, the ash of green Coleus leaves was 
6.41 per cent P,O,, while according to PALLADIN (40) the ash of 
beech leaves was 7.80 per cent P,O,, and according to Jost the 
ash of tobacco leaves was 4.66 per cent P,O;. Of the dry weight of 
TABLE VII 
PHOSPHORUS 
S le Sam Sample = doe 
am Ss rus 
Leat ct no. cd no. Average hat 100 4m. 
dry weight 
Gree 0.0. 
Cees cae Oa .O31 0.032 0.019 0.027 0.308 
Mottled Ao O.OIr O.OII 0.010 OIL o.181 
mote Bo 0.010 0.010 O.O11 0.011 0.176 
the green Coleus leaves, 0.91 per cent was P,O,, while according to 
PALLADIN pea leaves had 1.67 and bean leaves 2.19 per cent 
P,0;. With mottling the total percentage of phosphorus in the 
leaf of Coleus calculated as P,O, (on ash basis) had decreased from 
6.41 to 2.88 per cent, or somewhat over 50 per cent. In the case 
of beech leaves, PALLADIN found that in May the P,O, content was 
32.4 per cent of the ash, while in October it was only 5.1 per cent. 
The percentage decrease of P,O, in Coleus leaves was.not due to 
an accumulation of ash, but apparently to the decrease in the 
P.O; before the leaf fell, for when one calculated the amount of 
P.O; present in the green and in the mottled leaves, there was 
always a reduction of 50 per cent or more, whether the calculation 
was based on dry weight, wet weight, or ash. This reduction in 
the phosphate content of Coleus leaves was similar to that found by 
Swart (48) for other leaves, and in all probability the changes 
