100 NORTH AMERICAN FLORA [VoLUME 7 
4. Uredo Rostrupiana Arthur. 
Melampsora arctica Rostr. Medd. Gronland 3: 535. 1888. Not Uredo arcticus Lagerh, 1889. 
O and I. Pyenia and aecia unknown. 
II. Uredinia amphigenous, or only hypophyllous, scattered, round, very small, 0.1-0.2 
mm. across, early naked, orange-yellow fading to pale-yellow, somewhat pulverulent, rup- 
tured epidermis usually inconspicuous; urediniospores ellipsoid or obovate, small, 13-16 by 
16-204; wall colorless, thin, 1-1.54, uniformly and rather closely verrucose, with fine 
papillae, pores obscure; paraphyses intermixed with the spores, capitate, smooth, 55-604 
long, heads 17-24 « broad, wall very thick, 3-7, peripheral paraphyses thinner-walled and 
more clavate. 
III. Telia amphigenous, or only hypophyllous, scattered, roundish or irregular, about 
0.3 mm. across, often confluent, scarcely elevated, reddish-brown becoming dull-brown, 
subepidermal ; teliospores prismatic or oblong, 9-14 by 29-38, rounded at both ends; wall 
smooth, cinnamon-brown, very thin, about 0.54, slightly thickened above, 1. 
ON SALICACEAE : 
Salix glauca I,., Greenland. 
Salix groenlandica (Anders.) Lundst., Greenland. 
Salix herbacea L,., New Hampshire; Greenland. 
TYPE LOCALITY : Christianshaab, Greenland, on Salix groenlandica. 
DISTRIBUTION : Arctic and alpine regions of ‘northeastern America. 
5. Uredo Bigelowii (I'htim.) Arth. Résult. Sci. Congr. 
Bot. Vienne 338. 1906. 
Melampsora Bigelowit Thiim. Mitth. Forstl. Vers. Oest. 2: 37. 1879. 
Lecythea macrosa Peck, Bot. Gaz. 5: 35. 1880. 
Melampsora paradoxa Dietel & Holway, Hedwigia Beibl. 40: 32. 1901. 
O. Pycnia amphigenous, scattered, or somewhat gregarious, minute, punctiform, pale- 
yellow, inconspicuous, subcuticular, conical, 60-80 in diameter, 40-50 high. 
I. Aecia chiefly hypophyllous, scattered or somewhat gregarious, small, 0.1-0.2 mm. 
across, oblong, pale-yellow fading to white, inconspicuous, formed between epidermis and 
mesophyl, soon naked, pulverulent, ruptured epidermis somewhat noticeable; aeciospores 
globoid, 15-22 by 18-27“; wall colorless, thick, 2-34, finely and evenly verrucose, with 
distinct papillae, pores scattered, noticeable. 
ON PINACEAE: 
Larix Lyaillii Parl., Alberta. 
II. Uredinia chiefly hypophyllous, usually on conspicuous yellow spots, scattered or 
gregarious, round, 0.3-0.5 mm. across, orange-yellow fading to pale-yellow, soon naked, 
somewhat pulverulent, ruptured epidermis usually inconspicuous; urediniospores globoid, 
15-19 by 17-24%; wall colorless, thick, 2.5-3.5 4, sparsely and evenly verrucose, with fine 
papillae, pores scattered, evident ; paraphyses intermixed with the spores, capitate, smooth, 
50-70 long, heads 22-25 broad, wall thick, 3-5, peripheral paraphyses thinner-walled 
and more clavate. 
Ill. Telia amphigenous, or sometimes partly or wholly epiphyllous or hypophyllous, 
scattered, roundish or irregular, about 0.5 mm. across, often confluent, slightly elevated, 
orange-yellow, becoming yellowish- or purplish-brown, subepidermal ; teliospores prismatic 
or oblong, 11-14 by 29-42, rounded at both ends; wall cinnamon-brown, smooth, uni- 
formly thin, 1 z. 
ON SALICACEAE : 
Salix alaxensis (Anders.) Cov., Alaska. 
Salix amygdaloides Anders, , Indiana, Iowa, Kansas, Montana, Nebraska, New York, Ohio, 
South Dakota, Wisconsin. 
Salix Bebbiana Sarg. (S. rostrata Rich.), Colorado, Montana, Wisconsin. 
Salix bella Piper, Washington. 
Salix Bigelowit Ait., California. 
Salix cordata Muhl., Maine, New York, Ohio. 
Salix cordata angustata (Pursh) Anders., Colorado, Indiana, Kansas, Montana, Nebraska, 
Utah, Vermont, Wisconsin. 
Salix discolor Muhl., Indiana, Michigan, Minnesota, Wisconsin. 
Salix ertocephala Michx., Maine. j 
