The Phytoptus of the Vine. By Prof. Giovanni Briosi. 191 
eggs destined to produce in spring the young phytoptus, who climb 
up upon the new vine shoots. In autumn, on the contrary, these 
animals emigrate from the leaves, in order to nestle under the 
bracts which cover the winter buds, and perhaps to the roots 
where Moritz found them in the months of January and February, 
and on which they would cause the same alterations similar to 
those caused by the Phylloxera vastatriz. Between buds, gathered 
in January (in the midst of the cylindrical and very long hairs 
which are found under the scales or exterior bracts for the pro- 
tection of the buds), I found a large number of these cecidozoids, 
a little lethargic, but alive, and disposed to activity when exposed 
to heat. 
In one bud I counted more than 200 animals, in another 212, 
in a third 112, and in a fourth 72, and I do not think I have seen 
them all. Analogous observations have been made by Thomas * 
on the buds of Pirus communis, Prunus domestica, Sorbus aucu- 
paria, Tilia grandifolia, Alnus glutinosa, Acer campestre, &c. ; 
and Sorauert found them alive between buds of trees which 
shortly before had been exposed to a cold of —18° R. 
At the first mild breezes in spring, and the swelling of the 
buds, the animals regain breath, and begin again to lay eggs, 
which they deposit direct on the young leaves of the developing 
bud; thus the young ones are scarcely born, when they find 
already within reach the food which nourishes them. With the 
first young leaves of the vine, indeed, are discovered the first 
galls under the form of small spots of a colour little different from 
the parenchyma of the leaf, scarcely raised on the upper sides, and 
which can be specially well discovered by examining the young 
vine leaf by holding it between you and the sun. 
The distribution of the galls on the plant is also regulated 
by certain rules, which particularly depend on the conditions 
of nourishment of the animal, that is to say, on the one hand, of 
the faculty and force of the organs taking the nourishment, and 
on the other, of the mode of production and development of 
the latter. Thus it is that one can observe in May, on the 
stems attacked by the Phytoptus (when the vines are in full 
force of development), 1st, shoots which only present galls on 
the original and exterior leaf of the bud, which produced the 
branch and remained at its base; 2nd, shoots in which the galls, 
besides on the base leaf, reappear along the branch in two or 
three spots, leaving long intermediate spaces with perfectly un- 
hurt leaves; 3rd, shoots at last, in which the galls have left unhurt 
almost all the principal leaves, that is, those directly attached to 
* Beitrage z. Kennt. d. Milbg. u, Gallm. Giebel’s Zeitschr., &c., vol. xlii, 
p. 517, and following ones. 
+ Hand. d, Pflanzky. p. 177. 
