Part 5, 1920] AECIDIACEAE 373 
II. Uredinia amphigenous, scattered, roundish or oblong, 0.1-0.5 by 0.1-1.5 mm., tardily 
naked, somewhat pulverulent, cinnamon-brown, ruptured epidermis conspicuous; uredinio- 
spores globoid or ellipsoid, 18-26 by 22-32 »; wall light-yellow or golden-brown, moderately 
thick, 1~2 », sometimes 2.5 p, moderately echinulate with low points, the pores 5-10, scattered. 
III. Telia amphigenous, scattered, roundish or irregular, 0.1~0.5 by 0.1-1.5 mm., long 
covered by the gray, tenacious epidermis, compact, becoming pulverulent, blackish, ruptured 
epidermis conspicuous; teliospores ellipsoid or irregular, 20-30 by 32-50 yu, rounded or truncate 
above, rounded or narrowed below, slightly consiricted at septum; wall dark cinnamon- 
or chestnut-brown, uniformly thick, 1.5-2.5 4, smooth; pedicel pale, fragile; mesospores few. 
This species morphologically is equivalent to Nigredo Zygadeni (Peck) Arth., except in the 
possession of two-celled teliospores. The two forms are separately maintained only for convenience, 
and should eventually be united under one name. 
: ON MELANTHACEAE: 
Anticlea elegens (Pursh) Rydb. (Zygadenus elegans Pursh), Alberta. 
Stenanthium occidentale A. Gray, Oregon. 
Toxicoscordion gramineum Rydb. (Zygadenus intermedius Rydb.), Wyoming. 
TYPE LocaLity: Banff, Alberta, Canada, on Zygadenus elegans. 
DISTRIBUTION: Northwestern North America. 
ILLustrations: Holway, N. Am. Ured. 1: pl. 6, f. 28a, b. 
Exsiccati: D. Griff. W. Am. Fungi 288. 
147. Dicaeoma mutabile (Ellis & Gall.) Kuntze, Rev. Gen. 33: 
469. 1898. 
Puccinia mutabilis Ellis & Gall. Jour. Myc. 5:67. 1889. 
O. Pycnia amphbigenous, scattered or in small groups, punctiform, honey-yellow, becoming 
brownish, globoid, 75-150 4 in diameter. 
I. Aecia amphigenous, closely grouped in orbicular or elongate clusters on brownish 
spots, cupulate-cylindric, 0.2-0.4 mm. in diameter; peridium yellowish or whitish, the margin 
recurved; péeridial cells rhomboidal, 19-25 by 25-30 yu, overlapping, the outer wall transversely 
striate, rather thick, 5-10 », the inner wall serrate or granular, thinner, 3-6 »; aeciospores 
globoid or angular, 15-23 by 18-27 u; wall light-yellow, 1.5—2.5 » thick, finely verrucose. 
II. Uredinia amphigenous, scattered, oval or oblong, 0.2-0.5 by 0.4-1 mm. or more; 
rather early naked, dehiscent by a longitudinal rupture, pulverulent, orange yellow, ruptured 
epidermis conspicuous; urediniospores ellipsoid or obovate, 18-23 by 24-32 y; wall yellow, 
rather thin, 1-2 u, finely echinulate, the pores 4-8, scattered. 
III. Telia amphigenous or caulicolous, many, scattered, or confluent in lines, linear or 
oblong, individual sori 0.2-1 by 0.3-2 mm., confluent often to 1 cm. or more, rather tardily 
naked, dehiscent by a longitudinal split of the epidermis, pulverulent, lead-colored or chocolate- 
brown, ruptured epidermis conspicuous; stroma absent; teliospores ellipsoid or variable in 
shape, 19-26 by 27-42 u, usually rounded above and below, slightly constricted at septum; 
wall cinnamon-brown, uniformly thick, 1.5-2.5 4, smooth; pedicel pale, short; mesospores 
very few, less than 1 per cent., ellipsoid or pyriform, 16-23 by 20-32 ; wall 1.5-2.5 u thick, 
uniform; pedicel light-yellow, short. 
This species agrees essentially with Nigredo aemula Arth., except in the possession of teliospores 
that are chiefly two-celled. The two forms are maintained separately for convenience, but should 
eventually be united under one name. 
On ALLIACEAE: . 
Allium brevistylum S. Wats., Wyoming. : 
Allium Geyeri S. Wats., Oregon, South Dakota, Washington. 
Allium textile Nelson & Macbr. (A. reticulatum Fraser), Colorado, Montana, Washington. 
TypPE Locality: Sand Coulee, Montana, on “Allium mutabile,” error for A. textile. 
DisrRrBuTION: Western North America, in mountainous districts. 
ILIWSTRATIONS: Holway, N. Am. Ured. 1: fl. 6, f. 29a, b. 
Exsiccatt: Barth. Fungi Columb. 3764; Barth. N. Am. Ured. 1356. 
148. Dicaeoma Allii (DC.) Kuntze, Rev. Gen. 33: 467. 1898. 
Xyloma Allii DC. Fi. Fr. 6: 156. 1815. 
Puccinia Allii Rudolphi, Linnaea 1: 392. 1829. 
Puccinia Alliorum Corda, Ic. Fung. 4:12. 1840. 
Puccinia rotundata Bon. Abh. Nat. Ges. Halle 5: 219. 1860. 
Puccinia Blasdalei Dietel & Holway; Dietel, Erythea 1: 248. 1893. 
