Parasitic Finu/i of Illinois. 18f> 



On leaves of Ambrosia frip'da : MeLeaii, July T), 2888, July 

 21), 2880, Auft-. 4, 2884: Ch;uui)aigii, Aug. 12, lOlV); Piatt, Aug. 

 17, IKH); Fulton, Oct. 8, 1784. Xanthiim strnniariiim : Mc- 

 Lean, July 4, 2887, July (), 2387, July 11, 2888, July 14, 5588; 

 July 2.9, 2885, Oct. 6, "l796: Tazewell, July 22, 2886: Cham- 

 paign, Aug. 13, 1041; Piatt, Aug. 17, 1128; McHenry, Aug. 

 22. 1205: Lee, Se]it. 8, 5719: LaSalle, June 19, 5286, Sept. 12, 

 1477: JoDaviess, Sept. 18, 5985; Rock Island, Sept. 21, 1611; 

 Union, Oct. 21, 1982. Oct. 25. 1998 and 2004; Pulaski, Nov. 4, 

 2249. 



Tn the s])ecinieus on Aiiihrosia. the s])ores are somewhat 

 thinner walled and more rounded than in those on Xanfliiin)/, 

 hut the difference is slight. 



P. tanaceti, DC. 



IL, in. Amphigenous, Sori mostly rather large, scat- 

 tered, often sprinkled over the entire leaf; uredospores glohose 

 to ovate, echinulate, 21-24 by 27-82 /x; teleutospores variable, 

 broadl}' oblong to broadly oval with rounded ends, usually lit- 

 tle constricted, smooth, or sometimes warty towards the apex, 

 the latter thickened or not, 21-27 by 84-60 ^; pedicel hyaline, 

 very long, two to four times the length of the spore. 



On leaves of Helianthus annims: Piatt, Aug. 10. 100(i; 

 Lake, Aug. 22, 1206, L, XL; Kane, Aug. 80, 1366, I.. IT.; Cook, 

 Sept. 8, 1468, L, IL: Rock Island, Sept. 27, 1601. H. rigidas: 

 McLean, July 26, 2297, Oct. 11, 1881; Piatt, Aug. 10,1004; 

 LaSalle. Sept. 12, 1491, Sept. 14, 1539, Sept. 16, 1557, Sept. 20, 

 1598. H. iinjJlis: Marion, Oct. 20, 1902. H. deca petal us: Mc- 

 Lean, Aug. 4, 2299, Oct. 6. 1799. HeJianthus s/ts.: Adams, 

 June 80, 5861, II.; McLean. July 15, 2801, July 29, 2300, IL, 

 TIL, Oct. 6, 1798, Oct. 7, 1822, 'Oct. 11, 1887, Oct. 18, 1871; 

 Cham])aign, Aug. 13, 1038; Piatt, Aug. 17, 1129; McHenry, 

 Sept. 20, 1160: Kane, Aug. 80, 1365; Cook, Sept. 5, 1437: Lee, 

 Sept. 11, 5784; LaSalle, Sept. 18, 149(), Sept. 14, 1541, Sept. 17, 

 1565: Stephenson, Sept. 13, 5835, IL, III., 5844, IL, IIL; Jo- 

 Daviess, Sept. 15, 5916, IL, IIL; Ogle, Sept. 23, 6146, IIL; 

 Rock Island, Sept. 21, 1612, IL, IIL, Sept. 26, 1665, Sept. 27, 

 1675: Henry, Sept. 28, 1723; Fulton, Oct. 1, 1766, Oct. 3, 1738; 

 Jersey, Oct. 18, 6291; Union, Oct. 21, 1904, Oct. 28, 2097. 



