104 Journal of the Mitchell Society [December 



21. Collybia lilacina n. sp. 



Plates 1, 22, and 23 



Solitary or gregarious and at times subcespitose, rather often with 

 Uttle undeveloped ones attached to the stem bases of mature ones. 

 Cap up to 7.5 cm. usually about 4-5.5 cm. wide, hygrophanous, de- 

 cidedly or very slightly umbonate, somewhat uneven, expanded, 

 margin striatulate when moist, even or nearly so when dry, flat or 

 bent down; surface smooth, like fine leather in appearance, the mar- 

 ginal third often rugose in youth, the wrinkles disappearing; color tan 

 with the center decidedly deeper and usually with a tint of lilac at 

 maturity. Flesh thin, only 1. 8 mm. thick at stem, whitish except at 

 center, which is brownish-lilac, tough, almost tasteless. 



Gills rather distant, variable in attachment just as in Clitocyhe 

 compressipes, sometimes deeply sinuate, most of them barely attached 

 and not at all decurrent, again squarely adnate in part and sinuate in 

 part and some slightly decurrent by a tooth, very easily separating 

 from the stem when attached, about 5-8.5 mm. wide, broadest near 

 stem, color a pallid tan or bright tan, then darker with brownish-lilac 

 tints and smoky on drying, many short, none branched. The surface 

 of. the gills is set with spiny cystidia which project about 20-25 [i. 



Stem very variable in length even in plants of the same size, up to 

 11 cm. long and 6.5 mm. thick at cap, nearly equal, usually twisting 

 in drying and becoming lined from top to bottom, tough and semi- 

 cartilaginous, firm, elastic; surface pruinose and often lined above, 

 smooth below, the very base enlarged and tomentose with the fine 

 white mycelium; color of cap, lilac tinted at maturity especially above 

 white at base; flesh strongly brownish-lilac, deepest colored within, a 

 large hollow cylinder in center from top to bottom. 



Spores (of No. 1818) white, elliptic, smooth, 5.2 x 7.8 \i. 

 Very young plants are nearly black, but soon become paler. The 

 lilac tints do not appear until maturity and deepen afterwards. This 

 change is peculiar and constant. Smaller specimens of the species 

 have very much the general appearance of Marasmius oreades, but 

 differ in the smooth hollow stem, tendency to lilac tints in all parts 

 at and after maturity, in not reviving well when moistened and in the 

 much larger size attained at times. The habit also is different, our 

 plants being solitary or sparsely gregarious, and growing in woods 

 and shrubl^ery and on bare earth, not in open grassy places. It also 



