EUROPEAN TRUFFLES 



though two or three others are sometimes 

 seen on the markets. The different edible 

 species vary considerably in size, but none 

 of these would average smaller than the size 

 of a walnut with hull removed. 



Counting from the beginning of the 

 ripening period, the earliest of the truffles 

 is perhaps T, cBstivum, which is found from 

 early summer until early autumn. T, 

 mesentericum and T, magnatum are found 

 during much the same period, with T, un- 

 cinatum as an essentially autumn species. 

 T. brumale and T, melanosporum are spe- 

 cies which ripen during the winter months. 

 Two forms may be briefly described, in or- 

 der that the characters of the plants may be 

 apparent. T, melanosporum varies from 

 the size of a small nut to that of a man's fist. 

 Specimens have been found weighing more 

 than one pound. The Vv^art-like surface 

 structures are somewhat pyramidal in form. 

 The fruit body is solid, and a cross section 

 of the ripe or mature fungus shows a brown 

 ground effect marbled by numerous irregu- 



193 



