MYCOLOGIA 
VoL. VIII March, 1916 No. 2 
TWO PARASITIC MUSHROOMS 
Edward T. Harper 
(With Plates 177-179, Containing 14 Figures) 
VoLVARiA Loweiana (Berk.) Pat. 
Specimens of this parasite on Clitocybe nebularis were found 
by a member of the Minnesota Mycological Society in the autumn 
of 1915 and sent to me by the president of the Society, Dr. Mary 
S. Whetstone. Several collections both of the parasite and the 
uninfected host plant were received, from which the accompany- 
ing photographs were made. The plants grew in an area about 
ten feet square on the ground among leaves about a cluster of 
waxberry bushes. The host mushrooms had been collected from 
this locality and eaten for four years, but the parasite did not 
appear until the present season. 
The host plants are deformed by the parasite and become irreg- 
ular masses, like the so-called abortive forms of Clitopilus abor- 
tivus and Armillaria mellea. Whether their structure is similar 
to that of the host of Pilosace algeriensis described below could 
not be determined from my specimens. The illustrations of the 
European plants show less malformation of the host. The Vol- 
varia appears as small, white, spherical bodies on the pileus of the 
host and has a normal development like that of Volvaria bom- 
bycina. 
The specimens agree in all essential characters with Maire’s 
description in the Bull. Soc. Myc. de France, Tome XXVII, fasc. 
4, and I can add little from my material. The spore measure- 
[Mycologia for January, 1916 (8: 1-64), was issued January 21, 1916.] 
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