1913] MATHENY—BROWN-ROT FUNGUS 419 
known today. Kunze and Scumupt (14) a little later referred it 
to Oidium fructigenum, under which name it received attention 
from many writers, among the first of whom should be mentioned 
EHRENBERG (10), COOKE (8), Dusy (9), and Fries (11). In 1822 
PERSOON (19) renamed this fungus Acrosporium fructigenum, a 
classification which was never accepted by other writers. WaALL- 
ROTHIO (29) placed it in the genus Oospora, calling it both O. 
candida and O. fructigena, while voN THUMEN (27) first classed it 
as Oidium Wallrothii, but later (28) changed it to O. fructigenum. 
The first writers to attach any economic importance to this fungus 
were VON THUMEN (28) and HALiier (13). ScHROTER (25) in 
1893, being confident of its ascomycetous nature, placed it in the 
genus Sclerotinia. This classification was confirmed in Europe in 
1904 by ADERHOLD (1). Norton (16) had first discovered apo- 
thecia in 1902. 
Sclerotinia cinerea was first described as Monilia cinerea by 
BoNorDEN (7) in 1851. He noted it forming small, gray, sometimes 
brownish conidial tufts on fruit. This species has many times been 
confused with S. fructigena, in fact many of the descriptions given 
the one could apply equally well to the other. SAccaRDo (23) 
in 1886 recognized Monilia cinerea, while ScHROTER transferred it 
to the genus Sclerotinia along with M. fructigena. WoORONIN (30) 
in his excellent study published in 1900 established beyond a 
doubt the fact that the species are distinct. This opinion is held 
by SorAvER (26). 
Difference between S. fructigena and S. cinerea 
Several points of difference between these two species have been 
cited by ADERHOLD (2, 3, 4), WORONIN (30), and others. Of these, 
the most striking are as follows: 
1. The conidia of S. fructigena are always larger than those of 
S. cinerea. 
2. There is a difference in shape of the conidia, those of the 
former having an elongated ellipsoidal form, while those of the 
latter are more rounded. : 
3. The conidial tufts of S. fructigena are light brownish-yellow 
or ocher and are always large, while those of S. cinerea are ash-gray 
