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month in a fashion for which I am unable to offer any explanation. 
For instance, it is practically 1 per cent. of the dry matter in 
August and September, but falls to 0-3 per cent. in October and 
November, rises somewhat in December but falls again in 
February, only to rise again suddenly to nearly 1 per cent. in 
March. All these figures were fully confirmed. The only 
suggestion I can make is that in the low Nitrogen “ A ”’ samples 
there were great variations in the Nitrogen content from spot 
to spot. But the whole of the samples were in each case taken 
from an area of about 12 square yards, and each sample consisted 
of practically all the pieces of Rhizome found in an area of about. 
a square yar 
It is to be noted that in both the “A” and “B” samples 
the percentage of Nitrogen found at the beginning of the growing 
season in early April 1918 was considerably higher than that 
found in any other sample at any time of year. The samples 
taken nearly a year later in early March 1919 did not in either 
case contain nearly so high a percentage of Nitrogen. This may 
have been an effect of season. The outstanding difference 
between the two sets of samples is the radical difference between 
the percentage of Nitrogen all through the season. There are no 
great differences in other aspects. The moisture in the two sets. 
of samples is very similar and varies somewhat similarly during 
the season. In both it increases from April to June, falls 
agg ep the summer, then rises slightly and falls again to 
in December and again rises considerably in 
February and March. 
The ‘“ Soluble Carbohydrates ” also vary somewhat similarly 
in both with the season, though for the reason already stated 
they are always lower in the ‘“‘B” samples, which are rich in 
nitrogeous matter, than in the “A” samples. As might be 
expected, they fall to a minimum in June, then increase 
throughout the summer when the frond has developed and 
carbon assimilation is active. The fibre also varies on somewhat. 
similar lines in the two series of samples throughout the season, 
and is on the average nearly the same in the two. The Ash is. 
made up of two parts, the genuine Ash of the rhizomes, and 
siliceous matter derived from the soil which is accidently present. 
If we deduct this siliceous matter, the average ash in each of the 
sets of samples amounts to almost exactly 1 per cent. of the 
original rhizomes or 3} per cent. of the dry matter, and though 
it varies somewhat irregularly from month to month it exhibits. 
no features calling for special mention. The ‘‘ Ether Extract ” 
also, which amounts on the average to between -8 and -9 per 
cent. in both sets of samples, shows no special features calling 
for comment. Why then si et the Nitrogen content exhibit. 
such a remarkable difference 
The late Professor Trail examined both the rhizomes and 
fronds and reported that he could find no botanical differences 
between the bracken growing at the two places and that both 
