BULLETIN OF THE BUSSEY INSTITUTION. 423 
is really beneficial. Our native vines have a luxuriant growth of 
leaves; and the danger is that, in our short summers, the grapes 
will not be sufficiently exposed to the sun to ripen. But the Peron- 
ospora arrives, with us, at a period when the vine has_ attained its 
growth for the season; the important point being then to ripen up 
the grapes which are concealed by the foliage. By shrivelling up the 
leaves, the Peronospora enables the sun to reach the grapes without 
loss to the vines, as is shown by the fact that the vines continue to live 
on, year after year, without apparent injury. Should the fungus be 
introduced into Central Europe, the case might be different. The 
foliage of Vitis vinifera is by no means as luxuriant as that of our 
own vines; the winters are warmer, the springs earlier, and the sum- 
mers much moister, than here; and it is quite possible that the advent 
of the Peronospora, by reason of the greater warmth and moisture, 
would be some weeks earlier than here, before the vine had attained 
its growth, and at a time when the leaves are needed for the work of 
absorption and assimilation. It might be that thé introduction of Pe- 
ronospora viticola into Europe would prove a repetition, on a small 
scale, of what has, unfortunately, already happened in the case of 
Phylloxera. The presence of Peronospora viticola is no protection 
against what is in this country called Oidium Tuckeri, for we have 
found both plants growing side by side on a leaf of Vitis cordifolia. 
The fungus we are now considering was probably first collected by 
Schweinitz, who erroneously considered it Lotrytis cana, Lk., in his 
“Synopsis Fung. Am. Bor.,” 2663, No. 25. In the Curtis collection 
is a Schweinitzian specimen marked Botrytis cana, on a grape-leaf. 
The specimen is well preserved, and there is no doubt of its being the 
genuine J. viticola. 'The species was named B. viticola by Berkeley 
and Curtis, from specimens collected in 1848, and distributed without a 
description by Ravenel in his “Fung. Car. Exs.,” V. 90. It was 
referred to by Caspary, in “ Monatsbericht der Berliner Akademie,” 
May, 1855; and by Sprague, in “ Proc. Bost. Soc. Nat. Hist.,” Jan. 6, 
1858. It was first described by De Bary, in the “ Annales des Sci- 
ences,’ 4th series, 20th volume, p. 125, 1863, as follows: “ P. viticola 
(Berk. et Curt.), mycelii tubi crassi, seepe constricti varicosique 
(haustoria non vidi). Stipites conidiferi fasciculatim e stomatibus 
emergentes, graciles, elati, summo apice parum attenuato brevissime 
semel bisve dichotomi v. trifurcati; sub apice ramos plerumque, 4—6 
