ELISHA MITCHELL, SCIENTIFIC SOCIETY. 49 
developing and before attachment 1s secured they are cov- 
ered with thin-walled cells, but old roots which have been 
attached to a host-reot for some time, appear to have en- 
larged while the walls of the epidermal cells have become 
thickened. It is possible that the newly developing root 
is capable of absorbing from the soil, while the older ones 
that have already made attachment are no longer able to 
absorb; but neither of these statements is yet definitely 
known to be true. And since the seedling plant of Buck- 
leya as I have recently found out by planting them, is 
thus able to exist for some time without the intervention 
of attachments, it is quite possible that not only the young 
plants of Darbya may do the same, but that newly devel- 
oping roots as well may possess this ability to derive nutri- 
ment from the soil. This, however, is merely conjecture. 
These roots showed few forks and no roots could be found, 
except those developed * the spring, which had not 
formed an attachment or were evidently broken, so it is 
probable that those roots which do not find attachment 
soon lose their vitality and die. 
Polygamous plants seem to mature fruit only when 
fertilized by staminate plants or perhaps by other seed- 
ling polygamous plants. Near Chapel Hill in the lower 
valley of Morgan’s creek polygamous plants are found 
for three or four miles along the narrow strips of alluvial 
soil that border the creek, but no seed are produced. This 
would seem to indicate that all the groups of plants along 
Morgan’s creek have a common origin and are vegetative- 
ly produced from a common stock. The staminate plant 
is not found near Chapel Hill. 
Near Salisbury, N. C., many groups of the sterile plants 
are to be found within an area of two or three square 
miles, but as no trace of a polygamous plant has been 
found within twenty miles of these groups I am inclined 
to trace these, as well, to a common plant and derived 
from it vegetatively. This view is further strengthened 
