6 io 
Journal of Agricultural Research 
Vol. XXVII, No. & 
Vibrissea hypogaea (Thum. & Pass.) Rich. 1881. (28.) 
Coniocybe pilacriformis Rehm 1892. (20, p. 36.) 
Roesleria pilacriformis (Rehm) Henn. 1895. (16.) 
Pilacre pilacriformis (Rehm) Boud. 1907. (4.) 
Pilacre pallida Boud. 1907. (4.) Not Calicium pallidum Pers. 1794 
{23, p. 20), nor P. pallida E. & E. 1900. (9, p. 59.) 
A lichen Calicium pallidum Pers. 1794 (23, p. 20 ), (Coniocybe pallida 
(Pers.) Fr. 1824 (jj, /, p. j), has also been confused with Roesleria hypo¬ 
gaea. The specific name “pallida” has been used frequently in combi¬ 
nation with the generic name Roesleria (R. pallida (Pers.) Sacc. (jo, p. 
299) to refer to a fungus thought at the time to be one of the Stilbaceae 
but which is in reality Roesleria hypogaea. 
Another fungus, nonascogenous, commonly called Pilacre faginea , or 
P. petersii in this country, has been regarded erroneously by various 
authors as a conidial stage of Roesleria hypogaea. It appears to have 
been first described as Onygena faginea Fr. The synonomy of this fungus 
so far as can be ascertained by a study of original descriptions and the 
literature is as follows: 
Onygena faginea Fr. 1818. (jo, p. 23.) 
Onygena decorticata Schwein. 1822 (31, p. 63.) Not Onygena decor - 
ticata Pers. 1799. (24.) 
Phleogena faginea (Fr.) Link 1833. (21, p. 396.) 
Pilacre friesii Wein. in Linnaea. 1834. (j7> P- 413-414.) (Not P. 
friesii Wein. in Flora 1832. (36, p. 438.) 
Botryochaete faginea (Fr.) Corda 1854. (7, pi • 9 , fig- 95-) 
Pilacre faginea (Fr.) B. & Br. 1850. (j, v. 3, p. 363 , pi. n, fig. 3.) 
Ecchyna faginea Fr. 1857. (jj, p. 131.) 
Pilacre petersii B. & C. 1859. (3, v. 3, p. 362.) 
Stilbum pilacriforme Rich. 1889. (29), not Coniocybe pilacriformis 
Rehm (20, p. 36). 
The grape rootrot fungus has been reported growing on the roots of 
various hosts such as Vitis, Malus, Pyrus, Cydonia, Prunus (almond and 
cherry), Salix, Tilia, Rosa, and Paliurus. 
From a r£sum6 of the literature, it would seem that the advocates of 
the parasitic nature of Roesleria as opposed to its saprophytic nature of 
growth are almost evenly divided. The following consider it parasitic: 
Lemonnier (J9), d' Arbois de Jubainville (j), Hennings (j6), Jolicoeur 
(J7, p. 219-224), Massee (22, p. 289 ), and Bayliss-Elliott and Grove (8). 
Gillot (14), von Thiimen (33, p. 210-212), and Prillieux (23) believe it to 
be somewhat parasitic, while it is thought to be nonparasitic by Ber¬ 
keley (2), Cooke (6), Laurent (18) , Viala and Pacottet ( 33 ), Hartig ( 13 , 
p. 83 ), and Verge (34). The results of the writer’s experiments show 
that when ascospores are sown in wounds the fungus can establish itself 
in living roots. 
CULTURES 
Cultures were made on various media from ascospores from the fruiting 
bodies of Roesleria on apple roots (PI. 1, A) collected in New York City 
in October, 1920, by Dr. Dodge. 3 Plates of cleared corn-meal agar were 
3 Dodge, B. O. A root-rot disease of apple seedlings. (Title) In Amer. Assoc. Adv. Sd. Pro¬ 
gram. 71st meeting, p. 32. 1918. A number of French crab-apple seedlings, obtained through a nursery, 
had been grown in pots for two years, then set out in the garden. During this time the plants had been 
inoculated with the pear-blight organism, and had been attacked somewhat by wooly aphids in the garden. 
Early in November in 1917 it was noticed that several of the little trees were falling over, due to the fact that 
thdr root systems had been destroyed by some rot. By digging down in the soil a few inches, partially 
decayed pieces of roots were found bearing numbers of ascocarps of Roesleria. The greenish mycelium ef 
the fungus was discovered at least a foot beneath the surface of the ground. Fruiting bodies of the fungus 
were found on roots of plants the remainder of the root systems of which appeared to be perfectly healthy. 
