Erysiphe 191 



species was sent from Milan by Balsanio to Dr. Montagne, under 

 the name of Oidiuin Tuckcri^ but it is a ver)^ different species, dis- 

 tinguished by the very peculiar shape of its spores. The length 

 about .0015. Balsamo*s plant grew on Vcrbasaim montmium. 

 No Erysiphe has at present been observed in connection with this 

 species. The same species occurs on strawberries, to which it is 



very destructive. See Gard. Chron., April 15, 1854/' 



In Berkeley's herbarium at Kew there is the specimen of 0. 

 Balsaniii from Monta^jne's herbarium referred to above, and the 



conidia here are more or less barrel-shaped, ranging from 2S-30 

 X 14-18 /i in size (Fig. 161). In the turnip mildew the conidia 

 are subcylindrical, with rounded, unconstricted ends, 30-40 x 13- 

 15 /^ produced singly on the conidiophores (Fig. 162). Probably 

 O, Bahainii on species of Verbascum is the conidial stage of 

 ErysipJic cichoraceanivi or E, taiirica ; the Oidiuni on strawberries is 



probably that of Sphacrothcca Jiunudi. 



After a careful search on the (9/^////;/2-infected turnips, referred 

 to above, I found on a few plants some scattered patches of the 

 perithecia of Erysiphe polygoni These perithecia occurred chiefly 

 on the stem and petioles, only very rarely on the leaves. The 

 perithecia are mostly gregarious in scattered patches among the 

 subpersistent mycelium and contain about 6 asci, with 4-5 spores. 

 The appendages are colorless, or occasionally one here and there 

 is colored, and are variable in number and length, usually about 

 2-4 times the diameter of the perithecium. The turnip crop was 

 \-ery poor, but as the plants were infested with '' green-fly" {Aphi- 

 des), it is impossible to say to what extent the inquiry was caused 

 by the fungus alone. The remedies given above for the " pea 

 blii^ht" would probably be equally efficacious here. 



- Var. sepulta (Ell. & Everh.). [Fig. 157] 



Erysiphe septdta Ell. & Everh. Bot. Gaz. 14 : 286. 1889. 

 E, cichoracearitm DC. Burn; Ell. & Everh, N. Amer. Pyren. 

 12 (form on Bigclovia graveolens only). 1892 ; Jones, Proc. Calif 



Acad. Sci. II. 5- 71^^ ^^9> 



Amphigenous ; mycelium evanescent or subpersistent ; peri- 

 thecia large, 140-220 /i in diameter, averaging 180 /i, cells indis- 

 tinct ; appendages numerous, rather short, delicate, colorless, hya- 



