192 The Phytoptus of the Vine. By Prof. Giovanni Briosi. 
the branch, and are found instead on the small leaves of the lateral 
small branches, growing out of the axils of the principal leaves, 
besides on the extreme end-bud of the shoot itself. This proves 
that the animal goes to lodge on the young textures which are 
still growing, probably because when the leaves are fully developed, 
their texture hardens so much, that the animal’s mandibles can 
pierce it no longer. 
And we owe probably to this circumstance, taken together with 
the other that the development of the plant in spring particularly 
seems to proceed more rapidly than the multiplication of the 
animal, that the disease does not cause all the harm to the vine 
which might be expected. In fact, we see that before the animal has 
multiplied to such a degree as to have to emigrate, for instance, to a 
lateral bud, the principal leaves of the stem are already developed 
in such a manner and way as no longer to allow the animal to rest 
thereon, and it leaves them, in fact, untouched, and goes higher up 
in search of a new bud. 
The invasion must be very strong if the plant cannot save 
a good part of its leaves. 
Thus, in fact, whilst in some vineyards in Favara the number 
of stems attacked by the galls was very large, there were very few 
in which the disease had spread to all the leaves. And where the 
evil was compassed within a certain limit, the plant did not seem 
to suffer much from it, whilst, however, on the stems which were 
almost totally invaded, the damage was so serious as to check the 
development of the fruit, the fruit buds having always remained 
so small that they could not arrive at maturity. The fundamental 
functions of the vine plant, as shown, that is, ass¢milation and 
respiration, are disturbed, and the sad consequences can, of course, 
not astonish us. 
However, the assertion of Landois,* that this disease is not less 
damaging to the vine than the renowned fungoid growth Ozdiwm 
Tuckeri, Berk., appears to me exaggerated. Certainly, if in one 
vineyard every year this disease should extend and augment in 
intensity, the products would be not a little dimimished. However, 
it is a fact in Italy (at least) where the disease is old, that (as far 
as I know) there are few examples of excessive damage. 
With regard to the remedies, Landois, assuming that at the 
end of autumn the animals die, suggests collecting and burning 
the leaves which fall in autumn and get dry under the plants, 
which leaves harboured the eggs from which are produced the 
animals in next spring; but after what has been said before, this 
remedy is insufficient, and perhaps is not worth anything (in dry 
leaves, gathered in December, I did not find any eggs, but only 
husks and dead animals, deformed and shrivelled in every case), 
* Memoir cited, p. 353. 
