248 
A FEW NOTES ON THE CHEMICAL COMPOSITION 
OF BEE BREAD 
By RvurH L. PHILLIPS 
During the past year I have been studying the growth changes 
in the nerve cells of the honey bee, Apis mellifica. Since nutri- 
tion plays a very important part in such changes throughout 
the life history of the insect I was interested to ascertain the 
chemical composition of the nitrogenous food of bees. This is 
popularly called bee bread, and consists mainly of the different 
kinds of pollen collected by the insects on their foraging expedi- 
tions which is mixed with a small amount of honey and wax. 
Such pollen is probably representative, in its chemical content, 
of pollen in general. Therefore I am giving the results of the 
chemical analysis in case they might prove interesting to bot- 
anists. 
The time at my disposal was not long, so it was impossible to 
make more than one analysis, but still this represents, in the 
main, several analyses, as each determination represents the 
average of a series, several samples being taken and the final 
results computed as the averages of these. Therefore, with the 
exception of the wax to which I will refer later, the following 
figures represent approximately the composition of such pollen 
as is stored by the average hive of bees in mid summer. The 
sugar content is undoubtedly high for pure pollen since a certain 
amount of honey is used in making the bread. 
Bee bread and bee's wax both oxidize at a low temperature. 
For this reason the water was determined by drying in vacuo over 
concentrated sulphuric acid, necessarily a rather slow process. 
Had the presence of wax been suspected I should have determined 
it in the same way. However when its presence was discovered 
there was only time for a hasty determination by drying in a 
water oven, so the figures for the wax are much too high. As this 
is in no way a food, acting probably as a preservative, it does not 
affect the analysis of the pollen as such. Dr. Phillips, Bee Expert 
for the Department of Agriculture, suggests that this wax may 
have come from carelessness in removing the pollen from the 
