432 ON DISEASES OF THE GRAPE. 
he fungus at first pervades the cellular tissue of the leaf; then, a few days later, the minute fungus stems pro- 
trude a the stomata (breathing pores) of the lower surface, forming little upright branching plantlets, which 
might be compared to a miniature spruce tree, singly not visible to the naked eye ; they bear at the end of the branch- 
lets the summer spores (conidia), which mature, are discharged, spread by wind or otherwise, and, when moistened, 
germinate with astonishing rapidity. Late in the season the fungus produces what are called the resting spores 
(cospores) in the interior of the leaf-tissues, and, while the others propaga the parasite in summer, these larger and 
more enduring ones keep alive through winter and insure its growt he following summer. Thus it is seen that 
the dead ‘aildorwed leaves, containing the resting spores, venily do one the germs for the next season’s mildew. 
These leaves ought to be destroyed by carefully gathering and burning them, or by burying them deeply in the ground. 
The direct destruction of the fungus has been often attempted, and by different means, einiecully ~ sulphur-sprinkling, 
but without any marked effect; a dry spell of weather, however, arrests it most effectually for the time being 
The Peronospora has since 1878 made its appearance in Europe, —like the phylloxera, renin "padres 
from this country, — and has added another terrible infliction on the wine-growers there, which threatens to be worse 
than the Otdiwm, which years ago used to decimate the grape crops of Europe. 
A words about this Oidiwm may be in place here. This is a mildew-like fungus which appears on the outside 
of the upper surface of the vine-leaves, and bears its fewer spores on smaller, not much branched, stemlets ; it destroys 
the vitality of the leaves, and with it the crop, just as our mildew does, Its resting spores are unknown and with its 
life-history we are not so well acquainted, but we know that ssl sprinkled over the leaves will destroy it. It made 
its first appearance, as far as it is known, about 1845, in gra at Margate, near London, and spread rapidly and 
destructively over a great part of Europe and the islands, suey Madeira, where the grape culture was almost 
annihilated by it ; but it seems to be now less common or less injurious than it was years ago, and may possibly have 
run its course, vant as other epidemics are apt to do. It is unknown where it originally came from ; some suppose 
that it originated in America, but it has never appeared here in the form under which it is known in Europe ; whether 
in another form, is still questionable among our best mycologists ; at all events we have thus far only one destructive 
fourm of mildew here, the Peronospora. 
he second great fungus pest of our vineyards is the Black Rot, Phoma uvicola. On the berries but never on the 
leaves or stems, generally about the time that they are full grown, in July or August, very rarely on half-grown berries 
in June, a light brown spot with a darker central point is observed on the side and not near the stem ; this spot spreads, 
and darker, shining nodules or pustules, plainly visible with the naked eye, begin to protrude above the epidermis ; at 
last the whole berry shrivels up, turns bluish-black and the pustules roughen the surface, and each one opening at its 
top emits a whitish worm-like thread, which consists of innumerable spores ang together with a mucilaginous coating. 
In this condition the spores are inert, but rain will dissolve the mucilage and liberate and wash down the spores, or 
they will with the dead berries fall to the ground.. What then becomes of ie whether they enter the soil, or how 
they propagate the fungus, is as yet unknown. At all events it seems advisable to gather all the affected berries, if such 
a thing can be done, and destroy them. 
In Europe they have another fungus disease of the grape, called in Germany Brenner, in France Anthracnose, and 
described under the name of Sphaceloma ampelinum, which by some authorities has been supposed to be another form 
of develoquiais of our Black Rot, above described ; this, however, seems very doubtful. We have, as it seems, never 
had the Sphaceloma, nor they the Phoma, The former attacks all the green parts, 2 young stems, or green berries, 
and forms open wounds which might be compared to ulcers, while our Phoma is restricted, as far as known, only to 
green berries, without breaking up the tissues or forming ulcers. The Sphaceloma seems to be an old disease in Europe, 
known already in the last century. Mycologists are now carefully studying these questions. 
* The use of sulphur, or crude carbolic acid mixed with quicklime, as a manure, was suggested by Engelmann in 1879. 
Proceedings St. Louis Acad. vol. iv. p. xxxix. — Eps. 
