THE COMMON TRUFFLE. 
499 
— in the mushroom, as an example, it is the mushroom spawn, 
— while the veins, the reproductive parts, contain in their cel- 
lular tissue minute oval capsules, with two or more globular 
yellowish seeds ; this curious structure having all the parts of 
nutrition and reproduction inclosed internally, instead of exter- 
nally, as in other fungi. Plate XXVII., fig. 4, exhibits this last- 
named structural peculiarity, figure 3, the outer or cortical coat ; 
and figures 1 and 2, sections of small truffles, natural size. 
In language somewhat more precise and scientific, we should 
say truffles are produced in this way ; the mycelium quickly de- 
cays and allows the fungoid body to grow on in an isolated condi- 
tion. About September the ground becomes covered with nume- 
rous white cylindrical, articulated filaments, not visible singly 
to the unassisted eye, but by their immense numbers and rapid 
growth readily seen, and found traversing the soil in every direc- 
tion. These white flaxen threads are continuous with other 
flocculent filaments of the same nature. In the young truffles the 
external layer is gradually consolidated, and in a short time the 
destruction of the flocculent filaments complete and lost in the 
young plant, which is soon isolated in the soil, and then the outer 
or cortical coat hardens, and ultimately has the appearance of a 
small nut. Thus, like other fungi, truffles are reproduced by 
spores, which give origin to filamentous mycelium and seed- 
vessels, the source of numerous offspring. Groups of spores 
are pretty objects; their stellate appearance reminds one of 
the Xanthidiae ; the mass of the full-grown plant at particular 
seasons is almost wholly made up of these bodies, the yellowish- 
brown coloured seeds. The observations of M. Vittadini had 
already indicated the curious arrangement of the black and 
white veins, which traverse the tissue of the truffle ; and the 
more careful investigations of the Messrs. Tulasne have clearly 
shown their relations and destination. 
The young truffle exhibits very irregular sinuous cavities, 
partly communicating with each other, and terminating some- 
times at a single orifice corresponding to a depression on the 
outside. As they grow older, the partitions which separate the 
cavities become thickened, and the tissue comprising their sur- 
faces is developed into a kind of longish soft hair,— tomen- 
tum, which obliterates them : hence result the two systems of 
veins; the one set coloured, corresponding to the partitions 
which separated the primitive cavities, the other white, forming 
the filamentous tissue, and filling up these cavities. The former 
are continuous with the external cortical layer or outer skin ; 
while quite internally they are made up of a network of fila- 
ments or elongated cells (see fig. 4), running in the direction 
of the cavities ; from this shorter filaments branch off, almost 
perpendicular to the first, and in the dilated extremities of these 
