484 



We have never been able to find anything corresponding to the 

 above description. Our specc. labeled V. laurina, C. & E., are V. 

 ceratophora, Tul., with sporidia 8-10 x IJ /i. V. mhdypeata, C. & 

 P., occurs on sassafras, but is still different. 



V. Mahaleb, C. & E. Grev. VI, p. 11. 



This is also unknown to us. Our specc. under this name are 

 Botryosphceria fuliginosa. 



V. qnerna, Curr. Linn. Trans. XXII, p. 279, tab. 48, fig. 141. 



Kxsicc. Rav. P. Am. 7+5? 



" Sporidia slightly curved, simple, linear, colorless, crowded in the 

 apex of the ascus." 



The spec, in Rav. F. Am. 745, on Myrica, is without perithecia. 



**** Stroma cortical, circumscribed, disk mostly white or cinereous. 

 {Leucostoma, Nitschlce). 



V. nivea, (Hoff.) 



Spharia nivea, Hoff. Veg. Cr. I, p. 26. 

 Spharia nivea, Pers. Syii. p. 38. 

 VaUa nivea, Fr. Summa, p. 411. 

 Exsicc. Fckl. F. Rh. 602.— Rab. F. E. 635, 2768.— Rehm Asc. 328.— Thum. F. Austr. 255. 

 Kriegr. F. Sax. 434.— Sydow, M. March, 283, 2959.— Ell. N. A. F. 869.— id. 2d Ser. 2120 

 — Desm. PI. Cr. Ed. i, 281. 



Stroma scutellate, dimidiate, 1-2 mm. across, adnate to the inner 

 surface of the epidermis, white inside, disk erumpent, white, truncate. 

 Perithecia 4^-10 in a stroma, circinate around a central spermogonium 

 or inordinate, globose, small, necks slender. Ostiola small, black, sub- 

 globose, erumpent in a circle around the margin of the white disk, or 

 oftener scattered irregularly. Asci clavat6, 35-45 x 5-6 //, subsessile, 

 8- or 4- spored. Sporidia allantoid, hyaline, not strongly curved, 7-9 

 X lj-l| /«. Sperinogonia mostly with a single central pore, radiate- 

 celled. Spermatia cylindrical, curved, 6 x 1 /i, oozing out in reddish 

 cirrhi. 



On Populus grdndidentata, Ohio and Nebraska, and on P. trem- 

 uloides, Montana and Colorado, on poplar, Pennsylvania and Carolina. 

 Schweinitz states that it is common on apple trees at Bethlehem, Pa. 



European specimens have as stated in Syll. &c, larger sporidia 

 12-14 X 3 /i. The specc. issued in N. A. F. 869 are mostly only sper- 

 inogonia or sterile. The only perfect ones we have seen are from Col- 

 orado and Montana. These agree with the European specc. in all but 

 their smaller sporidia and rather smaller asci. This species seems to 

 attain perfect development only in high latitudes or in mountainous 

 regions. 



