232 



Mycologia 



mabundum group which now includes four or five well marked 

 forms in the United States : the typical form illustrated in the 

 Trans. Wis. Acad. Vol. XVII, pi. LXXVII, C, Hypholoma 

 echiniceps, pi. LXXVTII, the present H. Storea var. caespitosum, 

 the form called by Peck H. aggregatum var. sericeum, N. Y. 

 State Mus. Bull. 54, p. 972, pi. 79, and the rugose form described 

 as H. delineatum. 



The characteristic mark of the group is the smooth purple- 

 brown spores 3-5 X 6-9 /x. Peck gives for Hypholoma aggrega- 

 tum 3-5 X 6-9 fi and for var. sericeum 4 X 7V2 /*. Beardslee's 

 specimens agree with Peck's. Jaap gives for Hypholoma Storea 

 var. caespitosum 4-4.5 X 7.5—8 /x. Atkinson's measurements of 

 the spores of Hypholoma echiniceps are 3.5-5 X 7~9 The 

 spores of my specimens of this form agree, except that I found 

 none over 8 ]x, long. Typical Hypholoma lacrimabundum had 

 spores 4-5 X 7-8 ji some of them shorter and broader, 5 X 7m, 

 and somewhat triangular, suggesting Hypholoma populinum Britz. 

 as noted below. W. G. Smith says the spores of Hypholoma 

 Pseudostorea are 2.5-3 X 5~7 ^ and Plowright gives for Hypho- 

 loma hypoxanthum 4-5 X9-n/x. These two species are con- 

 sidered synonyms of Hypholoma Storea var. caespitosum and 

 show the extreme variations in the size of the spores provided 

 that the reports of the measurements are accurate. 



I have illustrated the spores of this group in pi. 12, C, which 

 shows spores from typical Hypholoma lacrimabundum, Hypho- 

 loma echiniceps and Hypholoma Storea var. caespitosum. They 

 are very different from the large tuberculate apiculate spores of 

 all forms of the Hypholoma velutinum group which are shown 

 in pi. 12, E. 



All the forms in the group agree in their essential characters. 

 The gills are dark, clouded, and with white, floccose edges. They 

 are usually weeping, though scarcely at all so in Hypholoma 

 Storea var. caespitosum. They become black with age. The 

 surface of the pileus is innate fibrous and usually tears into tufts 

 of fibers which are darker colored than the background. The 

 stem is hollow and more or less scaly like the pileus. The gills 

 are adnexed and the flesh is solid and whitish. 



The forms differ in size, more or less caespitose habit, shade 



