1916] Gilkeij: A Revision of the Tuherales <>f CaJifoniia 281 



tests of their edibility have been made. At present writing, however, 

 specimens of Geopora magnifica, a large species measuring from four 

 to ten centimeters in diameter, have been sent in from Alameda, Cali- 

 fornia, the discoverer, Mr. A. A. Baroteau, having for some time col- 

 lected and eaten the plant and esteemed it as an article of food. 



Of the true Tnhers found in our state, none are closely related to 

 the common edible truffles of Europe. Tuher aestivum of England, 

 T. hnimale of France, T. magnatum of Italy, and others, all so-called 

 "black" or "queen" truffles, are dark brown or black, with the surface 

 covered by large pyramidal or shield-shaped warts. The "white" 

 truffles of Europe are lighter-colored, with a smooth, or at most a ver- 

 rucose surface ; and Avhile some of these are eaten, they are in much 

 less demand than the former. The Tubers thus far reported from 

 California are all "white" truffles, but apparently even of these we 

 have none of the European species. None of our species exhibits any 

 marked odor, and since the truffle is used as a condiment and valued 

 for its flavor rather than for any nutritive value it may possess, it is 

 probable that ours will not prove of great economic importance. 



V. MORPHOLOGY AND PHYLOGENY 



Owing to the difficulties in the way of securing early stages in the 

 life-history of hypogaeous fungi, the relationships of the various 

 genera with each other and with other orders is still largely a matter 

 of conjecture. The latest arrangements of the ascomyeetous forms 

 are those of Fischer (1897a, p. 279; 1908, pp. 142-161), and Bueholtz 

 (1903, pp. 161-164). It will be seen from the text of all three that the 

 arrangements have been based principally upon the structure of 

 mature ascocarps rather than upon development. In a few' species 

 moderately young ascocarps were studied, Tuher excavatum and T. 

 puherulum by Bueholtz (1903, pp. 154^158), and Piersonia hispora 

 (the species at that time unnamed) by Fischer (1908, pp. 149-154). The 

 latter also figures in Rabenhorst's Kryptogamcn-Flora von Deutsch- 

 land (V Abtheilung, p. 8) an immature ascocarp of Genea sphaerica. 

 No statement is found concerning the age of the specimen from which 

 the draw'ing w^as made, and the fact tliat no notes in regard to de- 

 velopment accompany llic illustration, except one refering to the 

 width of the apical opening, would perhaps indicate that the ascocarp 

 was too nearly mature to reveal much of value in the way of changes 



