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earth; and it has been observed, that the trees became better fruit-bearers. 
In some situations it is possible, this might be the cause of the new prolific 
property of the trees; but I suspect it has occurred generally from the 
difficulty opposed to the number and elongation of the root-fibres, and 
consequently to the generation of the new caudexes of the embryon leaf-buds; 
whence a greater production of flower-buds ensued. 
In similar manner it is asserted by one of the Linnean school, in the 
Amoenitates Academics, that some bulbous rooted plants, which seldom 
produce seeds in Sweden, will produce prolific seeds, if their roots be 
confined in a garden-pot, till they crowd each other; as those of the Lily of 
the Valley (convallaria). And that the Orchis will bear prolific seeds, if 
the new root early in the season be severed from the old one, which has put 
up the flower-stem.* This must occur, says Dr. Darwin, in the former case, 
from the difficulty which the plants find to generate new offsets at their roots, 
which are their viviparous progeny; and in the latter case from the new offset 
being destroyed; whence, in both situations, more nutriment is expended 
on the flower. 
If the orchis , continues Dr. Darwin, could by such means be cultivated 
from seed on moist meadows or morasses, it might become a profitable article 
of husbandry; as when it is scalded in boiling water, and the peel rubbed off, 
it is sold by the name of salep, and might become a nutritive article of diet, 
like sago and vermicelli, if it could be propagated with less uncertainty. 
On the same account it is probable, that confining the roots of cucumbers 
and melons in small garden-pots would stop the too luxuriant growth of 
their leaf-buds, and render them sooner oviparous (seed-bearing), if care 
be taken to supply them with water more frequently, and with sufficient 
nutriment by mixing with the water some of the carbonic black fluid, which 
has drained from a manure heap. 
The Greater and Lesser Periwinkle (Vinca Major et Minor), Butter 
Burr (Tussilago Petasites), and many other plants, as remarkable for 
the sterility of their seeds as their great increase by roots, might, in all 
probability, experience a similar effect, if under similar circumstances; their 
* This law of Nature, however, does not appear general, for many plants producing offsets, or 
suckers, do accomplish the perfection of their seeds, as the Houseleek (Sempervivum Tectorum), 
the Stonecrop (Sedum), the Couch-grass (Triticum Repens), the IFillow-herb (Epjlobium), 
which last is a great runner, &c. &c.; and seeds also have been found prolific in the Lilies of the 
Valley, and the several kinds of Orchises, at least in this country. 
