488 
THE GENUS 1MPATIENS. 
supported by two courses of broken bricks, built 
all round, close to the rim inside of the pot, so 
that the atmosphere might not be excluded 
from the soil in the pot. If a great layer of 
soil had been placed all over the surface of the 
pot at one time, it would have materially in- 
jured the roots. The plant was never watered 
with liquid manure, nor by any other way but 
that of sprinkling the foliage, and occasionally 
the surface of the soil, with the syringe, at the 
time of closing the house, and the fruit has 
again been cut this autumn, (1843,) and 
weighed 6 lbs: the weight of all the fruit is 
avoirdupois, not troy." 
Impatiens Cr,ccineum. 
THE GENUS IMPATIENS. 
ITS VARIETIES, CULTURE, AND MANAGEMENT. 
The genus Impatiens derives its name from 
the peculiar irritability of the seed-vessels, 
which suddenly and forcibly collapse on being 
touched when they are nearly mature ; in 
doing so, they burst open and scatter the 
seeds in all directions to a considerable dis- 
tance. It is from this peculiarity in the seed- 
vessel that the common British species has 
received the specific name Noli-tangere, or 
Touch-me-not, a name which, though particu- 
larly applied to this individual plant, is equally 
applicable to the others of the genus ; all of 
which, as well as the allied genus containing 
the garden Balsam, exhibit the same charac- 
teristic. 
This property of irritability is lodged in the 
five elastic valves of the fruit, which are very 
slightly attached at the base, and separate, 
when ripe, on the slightest touch, and spring 
back with great elasticity. The cause of the 
phenomena may be thus accounted for : — The 
tissue of which the valves of the seed-vessel 
is composed, consists of cellules, that very 
gradually diminish in size from the exterior 
to the interior surface ; the fluids contained 
in the outer cells are the most dense, and, by 
a process of infiltration through the sides of 
the cells, they gradually empty the inner cells 
and distend themselves. In consequence of 
this, the external tissue is disposed to expand, 
and the internal tissue to contract, as soon as 
anything occurs to destroy the force that 
keeps them straight : this at last does occur 
by the disarticulation of the valves and ad- 
jacent parts ; a sudden spontaneous movement 
follows, and each valve rolls rapidly inwards, 
and with such force, as to eject the seeds to a 
considerable distance. That this is somewhat 
near a correct explanation of the process, 
appears from a counter experiment tried by 
Dutrochet, an acute and accurate physiologist, 
who proved that it was possible to invert this 
phenomenon by causing the fluid in the cells 
to filter in an inward instead of an outward 
direction. In order to effect this, he placed 
fresh valves of Impatiens into sugar and 
water (a fluid denser than that contained in 
the cells), and this gradually emptied the ex- 
ternal tissue, and, after rendering the valves 
straight, ultimately curved them backwards. 
There are two species found wild in Eng- 
land, one of which only, however, is generally 
considered as being truly a native plant ; the 
other (I. fulva) is a North American plant, 
and although now quite naturalized in many 
places, as, for instance, on the banks of the 
Wey, near Guildford, in Surrey, it was pro- 
bably originally an outcast from some garden. 
Other species are found in North America, in 
Siberia, and in Denmark. India swarms with 
handsome species, nearly all of which are de- 
serving of cultivation. According to Dr. 
Wight, at least a hundred species occur in. 
those districts from which Roxburgh described 
