120 MONTAGNE ON 



name of Circiuobolus Florentinus, a genus, founded on the presence 

 of the pycnidia, which did not differ from Ampelomyces quisqualis, 

 instituted some time before by Cesati on the same character.* I 

 participate in the opinion of Tulasne, who considers the genus 

 Byssocystis, Riess {Hedwigia, J 858, p. 23, tab. III., fig. 2, d.) as 

 belonging to this form of the fruit of Oidium. Finally I perceive 

 from the report of Victor Rendu, that Dr. Castagne had proposed 

 the name of Leucostroma infestans (not Leucostoma as erroneously 

 printed) ; a sad instance of the injurious practice of overloading 

 nomenclature with new synonyms which teach nothing. 



In the course of last April, M. Tulasne published a memoir 

 in the Botanische Zeitung, entitled De Erysi])his anhnadversiones, 

 in which he recorded the result of his observations on the fruit of 

 Erysiphe. The communication which he has just made to the 

 Academy (Oct. 17, 1853) is a sort of recapitulation of that memoir 

 with an especial reference to the vine mildew. 



M. Tulasne considers Oidium leucoconium, Erysiphoides, 

 Tuckeri, &c. as mere forms of fructification of the genus 

 Erysiphe, of which there are occasionally three ; 1, Acrogenous 

 spores ; 2, pyxidia, the fructification described by Amici ; 

 3, peridia, or ascophorous fruit inclosing spores contained in 

 transparent utricles known by the name of asci. Having esta- 

 blished the presence of three kinds of organs of reproduction in 

 certain species of Erysiphe he concluded tliat those which exhibit 

 one or two only as E. Martii LSv., communis Fr., lamprocarpa 

 Duby, are no less true members of the genus. And on these 

 principles he includes, not without reason, our Oidium in the 

 genus. If, as everything seems to show, M. Tulasne is right, 

 should I not be correct, as I at first intended, in considering my 

 genus Capnodium, which attacks the leaves of oranges and many 

 other trees, as the most elevated form of Antenuaria Lk. since it 

 is ascophorous, and only differs from Antennariaas Erysiphe from 

 Ampelomyces ? 



I may mention a matter here, which, though apparently 

 foreign to the subject, seems to me to have some relation with 

 those different forms which the fructification of one and the same 

 fungal can assume ; I mean that of Eurotium lateritium found on 

 the garrison bread by Dr. Rayer, in the peridia of which I have 

 detected asci containing spores, though this genus was previously 



*' He did not, however, perceive like Amici, tliat it was connected with 

 Oidium Tuckeri. 



