TRUFFLE. 
flesh. Upon the first production of the esculent 
truffle, its size is scarcely perceptible. As it 
proceeds in its growth, the earth that is around 
it is pressed together and pushed off, and on this 
account the truffle can prosper in none but a 
loose soil. If the soil is everywhere equally 
loose, the truffle assumes a globular form; but 
this is changed, if there is on one side a greater 
opposition than on the other, as, for instance, by 
a root or a stone. Where the soil is most moist, 
whether above or under the truffle, there it will 
either rise up or sink deeper. The degree of 
power of attraction of the moisture in the earth, 
to that in the truffle, necessitates such a change 
of place. In moist summers and in wet winters, 
truffles are found near the surface, and even pro- 
jecting above it, while in dry summers, upon 
poor dry places in woods, they have often to be 
dug from a depth of more than half afoot. Here 
is imposed upon them a greater pressure of su- 
perincumbent soil. If the earth is not very 
light, they cannot be fully developed, and there- 
fore remain small. The largest are, consequently, 
in general, found not deep under the earth, and 
in shaded light soil that is somewhat moist. 
These, however, are not so well tasted as those 
of middling size; they are also usually injured, 
and therefore of a bitter taste; for the access of 
their enemies, worms, snails, and quadrupeds, is 
much facilitated when no deep stratum of earth 
protects them against these attacks. 
Of all species of trees, an oak standing aloof 
from other trees with its branches widely ex- 
tended, collects about it the greatest number of 
edible truffles. It keeps off the burning rays of 
the sun, but at the same time permits the free 
co-operation of the air and of warmth. Under 
it, truffles acquire the most delicious flavour, 
and sometimes are so large as to be three or four 
inches in diameter and to weigh from a pound 
toa pound anda half. Truffles are also dug up, 
in woods that are not crowded, under hornbeams, 
elms, maples, and other deciduous trees; but 
less plentifully, not so well-flavoured, and less in 
size. In close pine woods they entirely fail, and 
are rare in woods of mixed kinds of trees. Hence 
vegetable mould from oak-leaves and decayed 
oak appears to contribute to the production and 
the growth of truffles, as advantageously as the 
dung of horses and asses does to the production 
of mushrooms. In the one case, a peculiar ani- 
mal matter produces the effect, in the other a 
peculiar vegetable matter,—perhaps the tannin, 
or some other yet undiscovered product of the 
oak-tree. The more of this matter any species 
of tree contains, with the greater facility are 
truffles produced in its vicinity, and in greater 
numbers. He, therefore, who wishes to lay out 
truffle-beds, must endeavour to accumulate this 
matter in the soil where he intends them to be, 
and to introduce those circumstances under 
which the production and thriving of this fungus 
are promoted. 
TRUMPET-FLOWER. 
TRUG. ‘A hod for mortar. 
TRUMPET-FLOWER,—botanically Benen 
A genus of ornamental, exotic, corollifiorous, 
| ligneous plants, constituting the type of the natu- 
ral order Bignoniaceze. See the article Branonra. 
A number of species formerly belonging to it are 
now assigned to seven other genera; and some 
of the best known and most magnificent of these 
are noticed in the articles Caranpa, Trcoma, 
SpatHopEA, and GreLsemium. But about 60 spe- 
cies which occur in British gardens still belong 
to it; and at least 20 more are known. Up- 
wards of a dozen of the introduced species are 
tropical, erect, evergreen shrubs and small trees; 
two are respectively hardy and half-hardy deci- 
duous climbing shrubs, from 10 to 30 feet in 
height ; and most of the others are hothouse 
evergreen climbers, varying in height from 4 to 
about 50 feet. Upwards of one-third have bi- 
nate, tendrilled leaves and one or few flowered 
peduncles,—some carrying their flowers race- 
mosely, and others paniculately ; about a dozen 
have ternate tendrilled leaves; a few have digi- 
tate leaves ; one has simple, cordate, fine-nerved 
leaves; and about ten or a dozen have either 
simply pinnate, bipinnate, or compoundly pin- 
nate leaves. About one-third have flowers of 
some shade or combination of yellow; and the 
rest have variously scarlet, orange, pink, purple, 
white, green, or variegated flowers. 
The capriolate or tendrilled trumpet -flower, 
Bignonia capriolata, is a native of North America, 
and was introduced to Britain in 1710. It is 
one of the hardy deciduous climbers, and makes 
a fine show in shrubberies and upon large trel- 
lises. It rises by the assistance of tendrils or 
claspers, and has commonly a height of about 
15 feet; its leaves sometimes come out singly, 
but generally in pairs, oppositely, at the joints, 
and are oblong, and continue so long in winter 
as to make the plant really a subevergreen ; the 
flowers come out from the wings of the leaves, 
and are monopetalous and bell-shaped, and have 
a very large tube, with an outspread and divided 
rim, and are large and of a yellow colour, and 
bloom in June and July, and are succeeded by 
short pods. 
The claw or quadrifoliate trumpet-flower, Big- 
nonia unguis, is a native of the West Indies, 
and was introduced to Britain in 1759. It is the 
half-hardy deciduous climber; and makes fully 
as fine a show as the preceding. Its branches 
are very weak and slender, yet wind about every 
thing near them, and sometimes rise so high as 
to overtop trees of from 20 to 30 feet in height, 
—and they are very tough, and have a smooth 
surface, and are often of a reddish colour, parti- 
cularly on the side next the sun; its tendrils 
grow from the joints, and are curved and tri- 
partite, and have a claw-like form; its leaves 
grow in pairs at the joints, and are four in num- 
ber at each, and have an oblong form, an ele- 
gantly green colour, and a very ornamental 
