214 Illinois Stole Lahoralonj of Xolaral History. 



M. salicina, Lev. 



II., III. Amphigenous, the uredo mostly hypophyllous, and 

 the telentoform more often epiphyllous. Uredosori small^ cir- 

 cular, often thickly spread over the leaf surface, surrounded by 

 a thick row of paraphyses, which are strongly enlarged and 

 rounded above; nredospores subglobose or elliptical, finely 

 echinulate, 12-15 by 14-18 ^; teleutosori various in size, usu- 

 ally flat, irregular, often thickly associated or confluent, crust- 

 like, becoming reddish brown or dark brown; teleutospores ob- 

 long, in transverse section polygonal, about 10 by 80-87 i^. 



'OnlenYeHolSalir corrlala: McHenry, Aug. 28, 1242,11., 

 Aug. 24, 1276 and 1271. S. longifolia: McHenry, Aug. 24, 

 1254, II., Aug. 81, 1896, II.. III.: Lake, Aug. 27,1850, IL, III.; 

 Lee, Sept. 11, 57SO, II.; LaSalle, Sept. 14. 2500, II., III.; Henry, 

 Sept. 28, 1707, II. Salix sps.: McLean, July 18, 2498, IL, 

 July 20. 2407, IT., Aug. 4, 2490. II. ; Piatt. Aug. 17, 1096, II. ; 

 McHenry, Aug. 24, 1278,' IL, 128S, II. : Lake, Aug. 27, 1851, IL, 

 III.; Kane. Aug. 80, 1875, IL, III,; LaSalle, Sept. 20, 1599, 

 IL, III.; Rock Island, Sept. 21, 1618, II. ; Jersey, Oct. 14, 6815, 

 IL, III.; Union, Oct. 24, 1977, II. ; Pulaski, Nov. 4, 2228, IL, 

 III. 



Thilraen thinks what is included in the above should be 

 separated into the following species, for which he has given 

 descriptions: M. Bigloivii. M. capreanum^ M. Hartigii, M. 

 mediisw, M. intdlimv', (Hedwigia XVIII. [1879] p. 77, and Bul- 

 letin Torrey Botanical Club, VI. p. 216). 



M. populina, Lev. 



IL, III. Amphigenous. Uredosori small, scattered over 

 the surfaces of the leaves, usually more numerous below, 

 circular, surrounded by a dense row of j)araphyses, which are 

 clavate or strongly enlarged and rounded above, powdery, 

 orange-yellow; uredospores varying from subglobose to oblong 

 or clavate, echinulate, 18-20 by 21-80 ^; teleutosori scattered, 

 mostly thickly studding both surfaces of the leaf, flat, compact, 

 crust-like, often confluent, reddish brown; teleutospores oblong, 

 prismatic, epispore thin, smooth, one-celled, 15 by 36-45 ^. 



On leaves of Popiihis treinuloides: McHenry, Aug. 20, 

 1196. P. Hionilifern: Tazewell, July 22, 2509, IL; McLean, 



