detached leaves of plan ts. 2gt 
similar to that which composes the tuberous roots of the 
plant. The enlarged parts of the leaf-stalks remained alive 
in the following spring; but whether they are capable of 
generating buds dr not, I have not been able to ascertain. 
Leaves of mint were planted in the same manner as those 
above-mentioned ; which grew r , and continued alive through 
the winter, and were still living in the end of the last month, 
having assumed the character of the thick fleshy leaves of 
evergreen trees. Upon examining the mould in the pots, I 
found it to contain very numerous roots, which must have 
derived their medullary, and their cortical, and alburnous 
substances from matter which had emanated and descended 
from the leaves. 
I had frequently observed, in former experiments, that the 
destruction of the mature leaves of young plants not only sus- 
pended the growth of the roots, but also the growth of the 
immature leaves ; whence I inferred, in a former communi- 
cation, that the organizable matter, which composes the young 
leaves, has always undergone a previous preparation in other 
leaves of the plant, either of the same, or preceding season ; 
and I was thence led to expect that, under favourable circum- 
stances, the mature leaves might be made to nourish and pro- 
mote the growth of immature leaves, without the aid of roots. 
Several shoots of the vine, each about a yard long, were de- 
tached from the trees, and laid over a succession of basins of 
water, into which each of the mature leaves was in part de- 
pressed ; and thus circumstanced, the young leaves continued 
to grow, and the points of the shoots to elongate ; and all 
were alive, and in perfect apparent health at the end of a 
month. The water necessary to preserve the young leaves 
MPCCCXVI. Q q 
