, 3 8 DISCOMYCETES [CH. iv 



The ascocarps of many species of Tuber are edible, the most esteemed 

 being T. melanosporum which does not occur in Britain. They grow chiefly 



Fig. 99. Tuber pubertilum (B. and Br.) Ed. Fisch. ; a. e. development of ascocarp ; a. x 52; 

 b. and c. x 28 ; d. and e.xii;/. section through mature ascocarp, x 6 ; all after Bucholtz. 



in soils consisting of sand mixed with clay and containing, iron, or in mixed 

 alluvium; the soil must be porous to secure sufficient aeration. 



Truffles occur in chestnut, oak, and especially beech woods and there is 

 evidence that they form mycorhiza with the roots of these trees. The relation 

 would appear to be of advantage to the fungus since the success of the culti- 

 vation of edible truffles under oaks in France depends on keeping the roots 

 near the surface. 



TUBERACEAE : BIBLIOGRAPHY 



1903 BUCHOLTZ, F. Zur Morphologie und Systematik der Fungi hypogaei. Ann. Myc. i, 

 p. 152. 



1905 FAULL, J. H. Development of Ascus and Spore Formation in Ascomycetes. Proc. 

 Boston Soc. Nat. Hist, xxxii, p. 77. 



1906 BOULANGER, E. Notes sur la Truffe. Soc. Myc. xx-xxii, pp. 77 etc. 



1908 BUCHOLTZ, F. Zur Entwickelung der Choiromyces Fruchtkorper. Ann. Myc. vi, 

 P- 539- 



1909 MASSKE, G. The Structure and Affinities of British Tuberaceae. Ann. Bot. xxiii, 

 P- 243- 



1910 BUCHOLTZ, F. Zur EntvvickelungsgeschichtedesBalsamiaceen-Fruchtkorpersnebst 

 Bemerkungen zur Verwandtschaft der Tuberineen. Ann. Myc. viii, p. 121. 



