ON ANTHRACNOSE — A NEW DISEASE OF THE VINE. 19 
The anatomical examination of a single grape showed an abun- 
dant mycelium, spreading through the whole of the substance of 
the tissue, and frequently ramifying. The peripheral portions of 
the grape contained the earlier stages of the mycelium. 
This mycelium is relatively large and black in colour ; the septa 
are numerous, and the articulations are filled with minute oleaginous 
globules ; it presents in places a felted appearance, the early state 
of a second form of fructification which has not arrived at maturity. 
These peculiarities of structure and appearance are those of a 
Pleospora or a Cladosporium. The leaves showed on their lower 
surface numerous conidiiferous tufts of a fungus belonging to this 
last genus, the nature of which I was able to ascertain. A trans- 
verse section of the leaf shows that the filaments proceed from 
the stomata, and escape in order to form their spores. The fila- 
ments are blackish brown, septate, ramifying but little, and produce 
at their extremities small spores either simple or multilocular. 
The spores are oval, and variable in form and diameter ; they are 
frequently elongated and acuminate at their point of insertion. 
The form, the dimensions, the nature of the spores and of the 
mycelium, of which in all their parts the diameter is ten times 
greater than that of the corresponding parts of the parasite which 
causes the anthracnose, prevents the supposition that these two 
diseases of the vine can have any relation to each other. The 
grapes are not attacked by the anthracnose in any definite spot, 
but it is near the point of attachment that this new disease first 
appears; by this peculiarity alone, one is enabled at the first glance 
to distinguish between these two diseases. 
It is probable that the vine disease of Etampes ought to be re- 
ferred to the Cladosporium , developing itself at the expense of 
living plants, in the same manner as that species which produces 
the speckled appearance on pears, and which has been studied 
lately by Monsieur Prillieux, a member of our Society.* Our 
species appears to be identical with the Cladosporium viticolum Ces.f 
This species does not appear to be of rare occurrence in our vine- 
yards. I have met with it several times, both in the plain of Mont- 
pellier, and at Cognac, during the numerous excursions I made 
through the vine district when engaged in my researches on the 
Phylloxera. 
The vines cultivated in these districts have generally cottony 
leaves, and the parasite which is found on the lower surface of 
the leaf, always covered with a thick down, forms greyish spots ; 
these spots are caused by the abundant spores, mixed with 
hairs twisted together. The presence of these grey spots is 
perhaps the only character indicating the existence of this 
fungus, of which the bad effects appear to be easily overlooked. 
I have never observed any bunch of grapes attacked and blackened 
# “ Comptes rendus de 1’Academie,” September, 1877. 
f “ Klotsch et Rabenhorst Fungi germ,” t. xix,, 1854, No. 1877. 
