398 BOTANICAL GAZETTE [JUNE 
percentages of cane sugar could be approached. The same is true 
also for glucose and fructose, for on the inversion of the cane sugar 
present they appear in approximately molecular proportions as deter- 
mined by Browner’s?? method. Occasional samples vary consider- 
ably from this relation, giving sometimes a large excess of fructose, 
sometimes of glucose. This may be explained in part by a number 
of possibilities. The difficulties of technic in taking consecutive 
representative samples of such material as pulped date must be taken 
into consideration because data from two different samples enter the 
Browne formula. An excess of fructose may be accounted for by 
the hydrolysis of inulin. S tape found inulase in some dates but has 
left no record of having found inulin. Neither inulin nor inulase was 
found by the writer in a sample examined in that regard. An excess 
of fructose over glucose might also originate in the preferential use of 
glucose by the tissues, as is known often to be the case. An excess of 
glucose might come from maltose and SLADE observed maltase, but 
I have not yet examined the date for that enzyme. Here again an 
excess of glucose might be consumed by the tissues, leaving nearly 
pure invert sugar. The relation between fructose and glucose in 
other fruits has never been worked out, but it appears that in the 
case of the date nearly all the sugar is cane sugar or a derivative of 
cane sugar. 
Times thus undoubtedly occur with every individual when the 
partial osmotic pressure of these three sugars is approximately 
equal; nevertheless, accumulation of total sugars goes on rapidly. 
The date, then, as a species at least, must be prepared to pass in 
carbohydrate against a relatively high osmotic pressure of cane sugar, 
glucose, or fructose, either singly or simultaneously. Unless we 
choose to hold that the intercellular threads of living protoplasm pass 
along colloids and crystalloids against osmotic pressure, we are forced 
to seek some likely soluble carbohydrate against which there exists 
no considerable pressure. This place seems to be filled by maltose. 
So far as I am aware, neither the presence nor the absence of maltose 
has been demonstrated in the growing date. We should never expect 
to find any great amount, and it might be so transient as to escape 
detection entirely. - 
3t Bur. of Chem. Bull. go: 10; also Jour. Am. Chem. Soc. 28:439. 1906. 
