MAY. 
103 
occasioned by conditions of soil, or weather, or situation. Altogether they made 
up a charming picture during the period of their brief existence. 
I have also a kind of ribbon-border on a small scale, that is particularly 
gay just now. Winter Aconites form a front row ; next is a line of the pretty 
blue Scilla sibirica, that in a shady position flowers remarkably freely, being 
profusely charged with spikes of flowers ; there is behind these a row of’ 
Primroses and Cowslips, all the common yellow varieties ; and as a back¬ 
ground a line of mixed Crocuses. 
Then about me are the singular-looking forms of the Persian Iris, with 
curious silver grey flowers having dark tips ; Daffodils; Van Sion double 
Narcissi, but a deeper-coloured and rather larger Daffodil; the large and showy 
Trumpet Major single Narcissus, with bright golden flowers; Campernelli 
Jonquils ; the gay Tournesol double Tulip; clumps of the white-flowering 
Iberis Tenoriana ; tufts of Pansies (poor Ophelia’s melancholy souvenir, “ There’s 
Pansies, that’s for thoughts ”); Alyssum saxatile, and some double Daisies. By 
clumping any of these in beds, or on borders, or by arranging them in lines, 
can there be obtained hi the early spring months a charming display, lasting 
nearly till the bedding-out season commences. R. D. 
ON THE FLOW OF SAP IN TREES. 
A writer in the last century observed that the “ Theory of vegetation 
should be studied by every one who purposes to make any proficiency in 
gardening and agriculture,” but though there has been much improvement in 
both since his day, still there is not, perhaps, one gardener in ten, or one farmer 
in a hundred, who follows his advice. However, for the sake of those who 
have not studied the subject, I may offer a few remarks upon it. The common 
belief is that the sap abends in spring, and descends into the roots of trees 
before winter. The latter is a vulgar error, which I shall notice afterwards, 
and writers differ in opinion respecting the former. It is certain, however, 
that sap does ascend in spring, and the modern belief is that it rises into the 
sap vessels by the mixing of the denser fluids absorbed by the roots from the 
soil, in a similar wav to that in which currents of fluids of different densities 
are transmitted by the process called endosmose. M. Dutrochet was the first 
to notice this, and the theory is spoken highly of by others; but without the 
aid of the capillary attraction of the sap vessels, and, perhaps, evaporation 
from every twig and leaf, his theory may be less satisfactory than that of De 
Saussure, who observes that “ the sap’s ascent is to be found in a peculiar species 
of irritability inherent in the sap vessels themselves .... and thus the fluid 
is propelled from cylinder to cylinder till it reaches the summit of the plants.” 
Either way, however, accords with the fact of roots sending up sap after the 
tops have been cut off close to the ground, or even below it, rendering the 
downward pressure of air from their tops, spoken of by others, useless; and as 
regards the sap being stored in the roots during winter, evergreens grow in 
wild winters, and deciduous trees are full of torpid sap. This may be seen by 
putting the end of a fresh-cut stick into the fire, when the juice will ooze out 
of the other end. If woodmen were to notice this fact they might see that 
summer is the best season to fell valuable trees, in order to let them lie awhile 
with their branches, that the leaves may draw off the sap. If this plan were 
generally adopted, perhaps there would be fewer complaints of “ sap wood ” 
and dry rot in timber, and the better quality of the Oak wood might make up 
for the loss of the bark, which can only be peeled off in spring. What used 
