312 University of California Puhlications in Botany [Vol.6 



In general characters as shape of ascocarp, smooth surface and 

 absence of pronounced base, this species seems to come near Tuher 

 foetidum Vitt. and T. australe Speg. The former as described, how- 

 ever, differs in the reddish-brown gleba, longer spores in comparison 

 to their width, larger and fewer alveoli, and probably in the very dis- 

 agreeable odor. It is impossible to determine from alcoholic material 

 the presence or absence of the latter character, but if it were as de- 

 cided in the Harkness material as it is said to be in the European 

 specimens of T. foetidum, it would doubtless have been mentioned by 

 Harkness. T. australe is described as " dirty- white, gleba white be- 

 coming gray, asci at first 2-3- then 1-2-spored, spores 35-38 by 

 45-50/a"' (Paoletti, 1889, p. 888), in all of these characters disagreeing 

 with our species. Its color and thickness of peridium, as well as the 

 distinct vein and spore characters, seem sufficiently important to keep 

 it as a distinct species. 



Tuber (Eutuber) monticoluin Hk. 



Plate 30, fig. 23 

 Proc. Cal. Acad. Sci., 3d ser., vol. 1, no. 8 (1899), p. 271. 



Ascocarp dirty white, 1.5 cm. in diam., lobed and wrinkled, sur- 

 face very minutely scabrous ; gleba white, netted with many small 

 veins ; outer cortical tissue pseudoparenchymatous, cells varying little 

 in size, walls not thickened, outer layer breaking away slightly in 

 places, making surface of ascocarp minutely scabrous ; pseudoparen- 

 chyma changing gradually to very loose, branched, irregular hyphae, 

 bordered below by close, more or less connected hyphae. becoming 

 pseudoparenchymatous in places; venae internae of similar structure 

 to latter tissue ; thickness of peridium variable, 280-640/i, ; asci semi- 

 globose, 64-80/t, 2-4-spored ; spores globose-ellipsoid, very minutely 

 alveolate, 11-14 bv 12-16 alveoli across diameters; spores 28-34 by 

 32-40/^. 



"Among firs in dense woods in Sierra Nevada ]\Its., at Towle, Placer 

 Co., Calif., July." No. 27, Hk. Col. Type. 



In cross-section this species appears somewhat like Tuher levissi- 

 mum, for the pseudoparenchymatous tissue of the cortex is very nar- 

 row, and the peridium (in places) is unusually thick; but the whole 

 structure is more delicate, the subcortical tissue is more irregular and 

 unconnected, the spores are much more minutely alveolate, and the 

 general appearance of the ascocarp — as observed from the two de- 

 scriptions — is very different. 



