402 BOTANICAL GAZETTE [JUNE 
in weight (or size) till something like 20 per cent. of dry matter is 
present. Growth, so far as size is concerned, has then about reached 
its limit, but accumulation of dry matter in the form of sugar now 
takes place more rapidly, and in a relatively short time the dry matter 
rises from 20 or 25 per cent. to nearly 60 per cent. During this time 
there appears to be little or no further increase in weight. The 
rational interpretation then is that water is replaced by sugar. Curing 
again increases the dry matter up to 70 or even 85 per cent., but this 
change is purely a loss of water. These observations are further con- 
firmed by purely practical ones. It may be observed that the indi- 
_ vidual dates on a bunch develop similarly throughout; the ones near 
the tips of the sprays remaining always somewhat smaller. At a cer- 
tain period the bunch as a whole appears much the same and indi- 
viduals begin ripening, but it may be a month or more before others on 
the same bunch, even on the same sprays, are ripe. The same thing 
is observed in artificial ripening experiments. Two sprays from the 
same bunch, and looking very much alike, will ripen under artificial 
conditions very differently. Some speedily develop into a plump, lus- 
cious fruit, while others dwindle away and finally furnish a thin skia of 
poor-quality flesh over an apparently normal seed. The seed seems 
to mature before marked changes in the ovulary begin. The fact 
that increase in dry matter takes place after the apparent maturity of 
the fruit must lie at the foundation of all economic attempts at arti- 
ficial ripening. Any plans which ignore this will necessarily prove 
futile. The ripening process in the date, unlike that in the banana, 
is essentially one of addition and not of transformation. By reducing 
results to the dry basis, the very important economic as well as scien- 
tifically interesting observations made above would be entirely lost 
sight of. Furthermore, it would magnify any errors of technic from 
two to six times or more. 
These objections cannot be raised, in like degree at least, to the 
method of expressing results by reducing percentages to absolute 
weight per date of each constituent at the several periods of develop- 
ment. It is evident, nevertheless, that this method also can give only 
a more or less distorted view, because it is practically impossible to 
select samples with any degree of assurance that they were of the same 
composition and weight as the previous sample at the time it was 
