414 Cultwation of Triijfles. 



burning rays of the sun by large oak trees, standing at a distance 

 from each other, but is not deprived, by thick bushes, of the 

 free access of currents of air. Where, in woods, there are 

 places bare of timber trees, and with but few bushes, or covered 

 with pollarded wood that does not stand thick, they thrive under 

 an oak, beech, whitethorn, and even under a fruit tree, and 

 sometimes attain the weight of from a pound to a pound and a 

 half: this unusual size, however, is only met with in moist warm 

 grounds. Here they lie nearer the surface of the soil. The 

 drier the soil is, the deeper they are produced in it; but are 

 usually so much the smaller : to this the vicinity of springs is 

 the sole exception. 



There are some varieties of truffles which differ in the gi'eater 

 or less degree of roughness of their external rind, in a stronger 

 smell, resembling that of garlic, and in a lighter or darker 

 colour. Amongst all truffles, the white variety is of most value, 

 and is preferred to every other. It grows in Upper Italy, chiefly 

 in Piedmont. Its surface is of a yellowish brown, or pale grey- 

 j'ellow, covered with protuberances resembling warts. The veins 

 in the inside are more delicate than in the black kind, and are 

 of a reddish yellow colour. Between the veins, the flesh of 

 truffles that are fully formed, and their sap-vessels and glands, 

 are of a reddish colour. The smell and taste of the white truffle 

 are much superior to those of the black, and on that account it is 

 more deserving of cultivation. Only the first plantation requires 

 to be circumstantially attended to, as living pieces can seldom 

 be procured, and to plant dead ones in new plantations is useless. 

 Since this white truffle never degenerates to the black, but con- 

 stantly produces the same, it appears to be not a variety, but a 

 particular species. It is also found in vineyards, meadows, and 

 even in ploughed fields ; but the black ones are found only near 

 to forest trees. 



2. Hog-TruJJle, Switic-Trujfle, Wild Tnrffle {Tuber stnlhmi). 

 — This truffle, which is generally kidney-shaped, usually reaches 

 the size of a bean, and only under very favourable circumstances 

 that of a small hen's egg. It has a thin, leather-like rind, which 

 is covered with many small round warts, without any flat inter- 

 stices. By means of these, it is distinguished from the true 

 truffle, which sometimes also assumes the kidney shape. The 

 flesh is juicy, and traversed by coarse veins, which are not very 

 crooked. The smell is disagreeably sour, and is like that of 

 swine's dunjr, on which account it has received its name. Its 

 taste is unpleasant and insipid. On account of its disagreeable 

 taste and smell, it is not used as food ; and none but avaricious 

 truffle-hunters mix it amongst the edible truffles, along with 

 which it is often found. There are, nevertheless, districts in 

 which none but swine-truffles are to be met with. Being hardier 



