1892. ] Fungi of Wild and Cultivated Plants. I15 
ous rust grows upon the low blackberry, dwarf raspberry, 
thimbleberry, wild red raspberry, high blackberry, and sand 
blackberry. In atrip through the Carolinas in May last, this 
orange colored fungus was to be seen at nearly all times from 
the car window and one could but pity the cultivated species 
of Rubus, were there any grown in that afflicted region. 
The diseases of the grape and in particular the mildew, Plas- 
mopara viticola (B. & C.) are in general common to all wild 
Species of the vine. The worst specimens I ever found were 
those of a wild plant in Iowa, many miles from any cultiva- 
ted vines and the mildew was so bad upon the canes as to: 
dwarf them to a few inches in length while they were cover- 
ed from one end to the other with the white down of the fun- 
gus. Not onlythe V7iz/'s @stivalts, V. Labrusca, V. vinifera, 
V. riparia and V. Cali ornica are infested, but likewise the 
closely related Virginian creeper and more recently the Boston 
Ivy are victims. 
Among the plums and cherries we find four parasitic fungi 
to interest us in this connection, for they abundantly illus- 
trate the fact of the close relationship of wild with our culti- 
vated plants. First the plum pockets, Exroascus Pruni (Fcl.) 
are familiar to all as peculiar distortions of the fruit and 
stems of the cultivated plum,’ dwarf cherry, bird cherry, 
choke cherry, and some other species of the genus Prunus. 
or shrubs, 
ae but not least for the genus Prunus is the black knot, 
ch plum, P. maritima Wang., a thorny shrub on 
age Sea-shore; the wild yellow plum, P. Americana 
the Sete shrub or small tree along streams. Of the cherries, 
quently « Cherry, P. Virginiana L., a small tree, is most fre- 
Y infested; but the wild black cherry, P. serotina Ehrh., 
