133 
having the appearance of glue 5 probably a pecu- 
liar modification of gluten. 
From 16 parts of hempseeds, Bucholz obtained 
3 parts of oil, 3 \ parts' of albumen, about If of 
saccharine and gummy matter. The insoluble 
husks and coats of the seeds weighed 6 ^ parts. 
The different parts of flowers contain different 
substances : the pollen, or impregnating dust of 
the date, has been found by Fourcroy and Vau- 
quelin to contain a matter analogous to gluten, 
and a soluble extract abounding in malic acid. 
Link found in the pollen of the hazel-tree, much 
tannin and gluten. 
Saccharine matter is found in the nectarium of 
flowers, or the receptacles within the corolla, and 
by tempting the larger insects into the flowers, it 
renders the work of impregnation more secure ; 
for the pollen is often by their means applied to 
the stigma ; and this is particularly the case when 
the male and female organs are in different flowers 
or different plants. 
It has been stated, that the fragrance of flowers 
depends upon the volatile oils they contain ; and 
these oils, by their constant evaporation, surround 
the flower with a kind of odorous atmosphere ; 
which, at the same time that it entices larger 
insects, may probably preserve the parts of fruc- 
tification from the ravages of smaller ones. Vola- 
tile oils, or odorous substances, seem particularly 
destructive to these minute insects and animal- 
cules which feed on the substance of vegetables ; 
thousands of aphides may be usually seen in the 
stalk and leaves of the rose ; but none of them are 
k 3 
