98 A Monograph of the Erysiphaceae 



Uncinula Bivonae Lev. Ann. Sci. Nat. III. 15: pi- 7-f- ^4- 

 185 1 ; Sacc. Syll. Fung. I : 6. 1882; Wint; Rabenh. Krypt. 

 Fl. Deutschl. i^ : 40. 1884; Jacz. Bull. I'Herb. Boiss. 4: 741. 

 1896. 



Etysiphe Bivouac Tul. Sel, Fung. Carp, i : 200. 1861. 

 ' Uncimda claiidcstina (Biv. Bern.) Schroet.; Colin*s Krypt. 

 Fl. Schles. 3 : 245. 1-893. 



Exsicc: Rab. Fung. Eur. 2030; Fckl. Fung. Rhen. 698; 



Rehm. Ascom. 400; Desmaz. PL Cr. Fr. ed. i, ser. i, 920, and 



ed. 2, ser. I, 220; Sacc. Myc. Ven. 617; de Thiim. Myc. 



univ. 755; Rab. Herb. Myc. ed. 2, 466; *Wartm. & Wint. 



Schweiz. Krypt. 824. 



Amphigenous : mycelium evanescent, or subpersistent as a very 

 thin effused film ; perithecia closely gregarious in small patches, 

 or scattered over the surface of the leaf, rounded-lenticular, 85— 

 115 fl in diameter, averaging 95 //, cells 10-14 /i wide : append- 

 ages i^vi^ 9-25, rarely 25—30, usually about 15, equalling or (usu- 

 ally) slightly exceeding the diameter of the perithecium, simple, 

 colorless, aseptate, or occasionally septate near the base, thick- 

 walled and usually rough below, thin-walled and swollen into a 

 somewhat club-shaped apex above; asci usually 4, rarely 3, 5, or 

 6, broadly ovate to globose, with or without a vety short stalk, 

 40-45 X 32-40 /■<, averaging 45 x 35 /^ ; spores 2, very rarely 3, 

 30-34 X 15-18 /^ sometimes slightly curved. 



Hosts, — V linns campestris, U, montana. 



Distrilnction. — Europe : England (239), France, Belgium (209)^ 

 Germany, Switzerland, Italy, Austria-Hungar}^, Poland, 

 Africa : Algeria. 



Asia : Japan. 



A well-marked species in the few, somewhat club-shaped ap- 

 pendages and the 2-spored asci. 



U, dandcstina is not known to occur in America, all the rec- 

 ords of its occurrence in the United States being erroneous, and 

 mostly referring to U. niacrospora. The plant recorded as U. 

 Bivonae by Cooke and Peck (90, p. 1 1) is U. Clintonii^ and the 

 host-plant is Tilia Aincricana, not Uluius as stated. The claim 

 of U. clandestina to be considered as British rests on the authority 

 of Cooke, who records (239) this species as growing on the elms 

 in the Royal Gardens, Kew; I cannot, however, find specimens 

 from this locality in this author's herbarium at Kew. The African 



