lf'16] Gilkeij: A Revision of the Tuherales of California 293 



"In forests, Auburn, Placer Co., Calif., ^Mav." 



No. 185, Hk. Col. Type. 

 "Under oaks. Wire Bridge, Placer Co., Calif., Feb." 



No. 129, Hk. Col. Type of B. alha. 

 "Tender Hcteromelcs arhutifolia. Auburn, Placer Co., Calif., Feb." 



No. 236, Ilk. Col. Type of B. filanuntosa. 



"Among decaying vegetation in slu'ubbv thickets. Auburn, Placer 



Co., Calif., "Uec." No. 231, Hk. Col. Referred to B. vulgaris. 



"Among slirubs under vegetable mold, Auburn, Placer Co., Calif., 



Dec." No. 222, Ilk. Col. Referred to B. platyspora. 



"Under shrubs in sandy soil, Auburn, Placer Co., Calif., Dec." 



No. 220b, Hk. Col. Referred to B. polysperma. 



"In soil under Cranofhus. Mill Vallev, ]\Iarin Co., Calif., Dec. 28, 



1902. ■• No. 33, U. C. Col. W. A. Setchell and C. C. Dobie. 



"Under Pin us radiata, U. C. Campus, Berkeley, Calif., Jan. 3, 1903." 



"Under Pinits. Apr. 1." "Under Pi)ius radiata. Mill Valley 



Calif., Jan. 23, 1904." No. 46, U. C. Col. N. L. Gardner. 



"Hvpogaeous under Piinis radiata; U. C. Campus, Berkeley, Calif., 



Nov. 19, 1904." "Under Arbutus Menziesii, Mill Vallev, Calif., 



Mar. 8, 1905." 



No. 212, U. C. Col. Type of P. Setchellii, N. L. Gardner. 

 "Under Ceanothus sorediatus in sand, near Golden Gate Park, San 

 Francisco, Calif., Mar. 23, 1905." 



No. 280, U. C. Col. N. L. Gardner. 

 ••Ingieside, San Francisco Co., Calif., Feb. 13, 1915." 



No. 404, U. C. Col. N. L. Gardner. 



Very noticeable variation is found in this species in color ; degree 

 of verrucosity of surface ; thickness of walls and extent of elongation 

 of cortical cells ; contrast between cortical and subcortical tissues ; and 

 «pore size and shape. Yet none of these are sufficiently defined and 

 constant to be used as specific characters. It was evidently upon these 

 characters that Harkness based his various species, but they must be 

 considered, I believe, merely individual differences ; for every degree 

 of variation, particularly in cell-form and in shape of spore, some- 

 times exists in a single plant. Colors range, according to Harkness, 

 from dirty white thi'ough orange and brown to black. However, the 

 plant in the Harkness collection labeled Balsamia alha is apparently 

 iiiiinature, which may account for its absence of color; while the 

 species B. nigra appears sufficiently distinct in structure to be con- 

 sidered a variety of P. magna fa. Tliis leaves the general range of 

 color for the species extending through orange to reddish brown, a 

 variation which is not uncommon in a single species of other genera. 



