296 University of California Publications in Botany [Vol. 6 



The compression has perhaps occurred in the process of sectioning, as 

 a result of thinner walls due perhaps to younger or less robust con- 

 dition or to something connected with the method of collection or pre- 

 servation. In any case, the plants appear identical in all other re- 

 spects, and this single dissimilarity has not seemed of sufficient 

 importance to separate them. 



While a specimen of this species is found in the Harkness collec- 

 tion under No. 151 referred to Choiromyces gangliformis Vitt. (Hk. 

 1899, p. 277), it is probable that this is not the plant which Harkness 

 had under consideration, for there is no possible means of reconciling 

 it with the description he quotes of Vittadini's species, even through 

 the first three adjectives: "Globosus, levis, fuscus. " If the original 

 and the present No. 151 are not identical, the locality quoted above 

 for that number is probably incorrect. Here, as in all other such 

 cases, critical notes added by Harkness would be of much value. 



Genea Vitt. 



Ascocarp verrucose, brown or black, globular or irregular in form, 

 with a variously shaped opening at apex ; cavernous, either with large 

 simple hollow or with connected labyrinthine canals formed by in- 

 folding of, or inward extending projections from, wall ; canals con- 

 verging at apical opening. Asci and paraphyses arranged in palisade 

 on inner side of wall. Hymenium rarely interrupted by strands of 

 sterile tissue, or conspicuously divided by such strands into "pockets." 

 Paraphyses slender, septate, uniting above asci to form secondary 

 cortex, latter generally narrower and somewhat more finely verrucose 

 than outer cortex, but similar in color and in pseudoparenchymatous 

 structure. Asci more or less regularly cylindrical, 8-spored. Spores 

 ellipsoid or globular, papillose, verrucose, or spinose. 1- or incom- 

 pletely 2-seriate, colored or colorless. 



The genus Myrmecocystis established by Harkness (1899, p. 269), 

 and further described by Fischer (1908, pp. 144-149), was originally 

 separated from Genea by the light color of the ascocarp ; spore sculp- 

 turing, shape, and size; and division of the hymenium into definite 

 areas. Several California n species, however, show such distinctly 

 intermediate forms of certain of these characters that their location 

 under the original arrangement is impossible. G. Gardncrii and G. 

 Harkncssii, for example, exhibit as definite division of the hymenium 

 as Myrmecocystis cerehriformis, while all other characters are typical 

 of Genea. Again, the compact arrangement of asci and fascicled para- 

 physes, as well as the very large globose spores ("Sdfx), of G. intermedia 



