THE AMERICAN BOTANIST. 
57 
nent in cheese making in certain places in England. But the 
secretion of ferments is carried on in all plants quite normally, as 
a few instances will show. 
When seeds are about to germinate the reserve food-materials 
contained either in the external endosperm (as in a wheat flour) 
or within the cells of the cotyledons, as of almonds, pears, and 
beans, consist of solid substances as starch and aleurone or liquid 
as oil, but in all cases they are unassimilable. Before the embryo 
can make any use of them they must be converted intO' a liquid 
state for absorption. This is done by means of ferments or 
"enzymes." by which starch is converted into sugar, and aleurone 
into peptones, etc. A precisely similar process has to be gone 
through when a potato' tuber sprouts, and its starch is to be util- 
ized for growth. 
Another case is where secondary roots arise from the mother 
root. They issue from below, and are therefore called endogen- 
ous. They commence as little bulging points which continually 
elongate till they finally issue out of the surface, raising up the su- 
perficial tissues like a collar around them. In passing through the 
cortex the root makes a hole for itself by dissolving the latter in 
its passage, and at the same time absorbing the nutritious solution 
for its own purpose of growth. It sometimes happens that the 
creeping underground stem of couch-grass meets with a tuber or 
bulb in its course. It does not pass round it as if round a stone, 
but bores right through the obstruction. In so doing the tip of 
the stem behaves like a secondary root, and dissolves out a passage 
for itself. — The Garden. 
NOTE AND COMMENT. 
Wanted. — Short notes of interest to the general botanist are 
always in demand for this department. Our readers are invited 
to make this the place of publication for their botanical items. 
Variation in the Pecan. — The pecan nuts, so plentiful in the 
fruit stores, is the fruit of the southernmost of our hickorys — 
Hicoria pecan. The tree is much like other hickorys in appear- 
ance, with a rather rough bark, but not so rough as that of the 
