The Phytoptus of the Vine. By Prof. Giovanni Briosi. 181 
mechanism well; I now find I had never before seen a row of 
teeth, shown clearly under the Exhibitor. I use it now for white- 
light illumination ; indeed, I scarcely use any other illuminator. 
It requires practice and patience to master its manipulation, but 
well repays it. p 
I have placed my models in the hands of Mr. Baker, of High 
Holborn, Mr. Curties having been here to see me work the instru- 
ment, and having lent me great assistance in getting lenses, &c., 
made for me. He has fitted one for me exactly as described 
above, and I find it perfect in use. I have no doubt but he will 
have them constructed at a moderate price, and show their use to 
anyone who may apply to him. 
I shall be more than satisfied if any of our Fellows get a tenth 
part of the pleasure I have had in the use of this little affair. 
That it may be capable of improvement I can conceive, and shall 
be most glad if it is so improved. by those who are more scientific 
than myself. 
SIDMOUTH. 
III.—On the Phytoptus of the Vine (Phytoptus vitis, Landois).* 
By Professor Giovanni Briost, of Palermo. 
Pirates CLXXVII. anp CLXXYVIII. 
Marcetio Matpieut has been the first to investigate scientifically 
this evil, which attacks many other plants besides the vine. 
This disease consists in a kind of protuberance which is formed 
on the leaves, which in consequence assume a characteristic speckled 
aspect. 
These protuberances, galls, or cecidii,t have, for the most part, a 
roundish or oblong, sometimes an irregular form, especially when 
through spreading they run one into another, assuming in conse- 
quence various sizes, so that leaves are found (at least at Favara) 
* Translated from the Italian by W. R. 
+ Professor Targioni Tozzetti proposes for this disease the name of Zrinosy 
(it was he at least who did, I believe), but to me the name of Phytoptosy seems 
more appropriate from the moment that it has been proved not to be due to a 
fungus (Zrinewn), as it was once thought, but to a mite (acarus), the Phytoptus. 
t{ As the word gal/ could probably be only applied to pathological products 
of more or less roundish form, Thomas, to whom we are indebted for most accurate 
researches about this disease, proposed ultimately to designate by the Greek 
word cecidium every abnormal formation (in which the plant takes part) of the plants, 
caused by parasites; hence diptera-cecidium, acaro-cecidium, myco-cecidium, &e., 
according to whether the galls are due to diptera, acari, or fungi, &e. Besides 
grouping in two large categories all these varieties, viz. those caused by attacks 
of parasites with negative cones, and those due to attacks in other parts of the 
plants, he called the first acrocecidii and the second pleurocecidii, and lastly 
ceecidozoids the animals, cecidophyti the plants producing parasitism. Beitrige z, 
Kennt. d. Milbg. n.d. Gallm. in Giebel’s Zeitsch. f. d. gesammten Naturwissen- 
schaften, vol. xlii. p. 517. 
