THE COMMON TRUFFLE. 
497 
prussic acid; phosphoric acid, potash, ammonia, albumen, pectine, 
and vegetable mucus, -with fungic skeleton. So that the odour is 
chiefly due to a peculiar yellow empyreumatic oil, not unlike spirit 
of hartshorn. M. Vittadini, of Milan, was among the first to make 
a more careful examination of the truffle, both of its external and 
microscopical characteristics, and succeeded in throwing a con- 
siderable amount of fight on its organization. His observations 
have been much extended by the researches of the Rev. M. J . 
Berkeley, Klotsch, Corda, and the Tulasne’s. Vittadini pointed 
out that these fungi presented two essentially different types. In 
the one, Hymenogastrece, the internal fleshy mass presents a 
number of winding cavities, lined by a membrane analogous 
to that which clothes the gills of the Agaric, and the superficial 
cells produce at then free extremities three or four spores, 
or seeds, which become detached, and eventually fill up the 
cavities. 
The other type, Elaphemycce, Tuberacece, comprising those 
of the truffle kind, and as may be surmised by the scientific 
name assigned to them — Tuber cibarium, — are plants charac- 
terized from the underground root presenting a fleshy mass, 
the outer surface of which constitutes the common envelope, or 
skin, termed the pericliwn, while the numerous narrow sinuous 
cavities are lined and in part filled up by filamentous tissue, 
mingled with cells of a peculiar form, and terminating in 
spores. 
To place the truffle among the class Tuberacece would appear 
to be a mistake ; for it can hardly be said that this curious un- 
derground esculent, a perfect plant destitute of leaves, stems, 
and roots, in any way resembles the genus Tuberacece, except in 
one unimportant particular, namely, external appearance. Every 
cell in the truffle is an assimilating surface ; the whole plant is 
a reproductive organ; and every part of the structure per- 
forms the functions which, in the more complex plants of the 
Tuberacece, are performed by organs specially set apart. 
The fungus genus, which claims the truffle, until very recently 
furnished us with but few varieties ; the more careful researches 
of the Messrs. Tulasne made throughout France, enabled them 
to extend a before limited fist to a hundred and forty-four spe- 
cies, comprehended in twenty-five genera of these plants. 
The whole family of fungi are developed from minute spores 
or seeds, which are continually carried about by currents of air. 
At length the seeds are deposited on a suitable soil : their 
growth is most rapid; when once rooted, they are extremely tena- 
cious of life, and exhibit considerable powers of resisting frost, 
as well as heat ; some seeds having been subjected to the boiling 
heat of water without losing their power of germination. 
Truffles prefer a dry, light, calcareous soil, in woody grounds. 
