Gilkey: Two New Truffles 



101 



coarsely pseudoparenchymatous, breaking away more or less at 

 surface, changing within to irregular open tissue consisting of 

 pseudoparenchyma and hyphae; sub-cortex of similar structure 

 but more compact, and forming origin of venae internae; thick- 

 ness of peridium 400-600^; venae internae similar in structure 

 to sub-cortex, hyphae 4-6 /x in diam. ; venae externae conspicuous, 

 long, branching, generally twice the diam. of venae internae, 

 similar in structure to inner cortical layer, hyphae 6 p in diam. ; 

 asci semi-globose, 48-56 by 56-64/*, 1-4-spored; spores yellow, 

 globose-ellipsoid, 20-38 by 22— 40 /*, alveolate, 3 by 4 to 6 by 7 

 alveoli across diameters, sculpturing 4-5 p thick. 



Beneath the surface of the ground, near oaks. No. 530, U. C. 

 Coll., L Robba & G. Giavelli. 



Material of this species was received from Dr. Fred J. Seaver, 

 of the New York Botanical Garden, and later from Mrs. Flora 

 Patterson, of Washington, D. C., the material in both cases, how- 

 ever, having been collected near New York City by L. Robba 

 and G. Giavelli. 



Of the European species of Tuber described, this apparently 

 comes nearest T. dryophilum, T. maculatum, and T. rapaeodorum, 

 principally in the general characters of ascocarp surface and of 

 spore. However, the specimens of this species examined differ 

 from descriptions of all three in the uniform color of the asco- 

 carp, that of the three European species mentioned being de- 

 scribed as mottled or spotted. The unusually thick cortex and 

 the 1-4-spored asci also distinguish our species from T. dryophi- 

 lum as described. In gleba color and number of spores in the 

 ascus, it differs from descriptions of T. maculatum; and from T. 

 rapaeodorum in the usual spore number in the ascus, in the shape 

 of the spores (the measurements cited for the spores of the latter, 

 i.e. 29-42 by 23-29 p, making them less nearly globose), and in 

 the characteristic structure of the cortex described above, that of 

 the European species as figured by Tulasne (Fung. Hyph., pi 18, 

 fig. 1 ) , having a distinctly pseudoparenchymatous structure with- 

 out, and hyphal structure within. It is thought best to consider 

 this, therefore, a distinct species. 



Agricultural College, 

 Corvallis, Oregon. 



