C. E. BROOME — TRUFFLES AND TRUFFLE-CULTURE. 17 



and imperfect microscopes, resembled somewhat a Truffle m 

 miniature, and early writers concluded that the mature plant was 

 merely one of these seeds largely developed in all directions. 

 The Tulasnes have proved, however, by careful observations that 

 they germinate in the same way as do those of most other Fungi, 

 viz. by giving origin to delicate threads, which spread in the sur- 

 rounding soil, and that from such threads the young Truffles 

 arise, probably after some kind of impregnation, which is as yet, 

 notwithstanding the researches of recent observers, involved in 

 obscurity. The fact of the existence of a mycelium in Truffles, 

 resembling that of Mushrooms, must be taken into consideration 

 in any attempt that may be made to cultivate them. 



The soils in which edible Truffles are found in France are 

 always calcareous or calcareous clays, which accords generally 

 with my own experience. Tuber mesentericum occurs, however, in 

 ferruginous sands, as is also the case with another species, Hydno- 

 trya Tulasnei, which, or a closely allied kind, is largely eaten in 

 Bohemia, under the name of Czerwena Tartoffle. Messrs. Tu- 

 lasne describe the soil of a Truffle district near Loudun, Vienne, 

 as composed of rolled fragments of calcareous matter, mixed with 

 fine quartzose sands, lying on a thick bed of compact marly clay, 

 which easily splits up into thin layers. It contains, in 1000 

 parts, 500 of calcareous matter, 325 of clay and iron, 150 of quartz- 

 ose sand, and 25 parts, more or less, of vegetable mould. But 

 they attribute a still greater influence in the production of these 

 plants to the presence of trees — a condition necessary perhaps to 

 their growth, in order to keep off the heat of the direct sun-rays. 

 Our authors testify, indeed, that this is not always indispensable ; 

 and I have seen Truffles dug up on the bare sloping sides of the 

 Italian mountains. 



Some persons have supposed that these Fungi are parasitic on 

 the roots of trees. This the Tulasnes expressly deny, on the 

 strength of observations and inquiries instituted to that end 

 and I can confirm them in this matter, and would remark that 

 the frequent presence of certain galls attached to the small roots 

 of oaks, resembling young Truffles so strongly as often to deceive 

 me for a time, may have given origin to this error. 



Some trees appear to be more favourable to the production of 

 Truffles than others. Oak and hornbeam are especially mentioned ; 

 but, besides these, chestnut, birch, box, and hazel are alluded to. 

 I have generally found Tuber cestivum under beech-trees, but 

 also under hazel, Tuber macrosporum under oaks, and T. brumale 



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