THE CULTURE OF OXALIS C REX AT A. 
205 
fore, conclude tliat plants generally have been formed for the climates 
to which they are indigenous, and have not that mutability of 
structure or of sap which would render them invulnerable to frost in a 
colder country, or to the incessant excitement of a warmer one without 
deterioration. 
That many plants are now seen in the open air which were formerly 
in the green-house or even in the stove is well known ; but this has not 
happened in consequence of any change in the constitution of those 
plants; but merely from being misplaced on their first introduction for 
want of experience :—the Aucuba Japonica, one of our hardiest shrubs, 
Avas once under our care in the warmest end of a conservatory! 
The effect of frost on tender vegetable bodies is mitigated by 
thawing it off Avith Avater before the sun shines upon them. This 
seems to contradict Avhat has been before stated, as to dryness being 
a safeguard to plants. But the cases are different; perfect dryness is 
a security against frost, but when plants are loaded Avith frozen deAv, 
and this alloAved to be dissolved by the sun, a much more intense 
degree of cold is generated during the solution of the icy particles by 
the sun, than if they were suddenly dissolved by Avater. It is this 
increased degree of cold Avhich ruptures the delicate vessels of the plants, 
and of course destroys them. 
Sometimes Ave see the stem of a slender shrub, as a heath, for instance, 
rent into many pieces, while the youngest shoots remain unhurt. This 
is OAving to the rigidity of the first, and the elastic texture of the 
second; the latter yields to the distending effects of the congealed sap, 
and afterAvards returns to a healthy state ; but the unyielding character 
of the old wood only renders it the more destructible. The foliage of 
the grasses indigenous to cold countries is only withered by frost, 
but seldom destroyed, OAving to the tenacity and elasticity of its 
structure. 
ON THE CULTURE OF OXALIS CRENATA. 
BY MR. PETER. JENKINS. 
Sir,— As the culture of the Oxalis Crenata appears still to interest 
some of the readers of the Horticultural Register, I have, at the risk 
of being considered officious, taken the liberty of addressing a feAv lines 
on the subject; not that I think any national advantage Avill ever arise 
from its culture, but Avholly to sIioav how tubers may be procured by 
those Avho are anxious to obtain them. 
