434 NORTH AMERICAN FLORA (VoLumE 7 
O and I. Pycnia and aecia unknown. 
II. Uredinia amphigenous, chiefly epiphyllous or caulicolous, scattered or occasionally 
confluent, roundish or elongate when caulicolous, 0.5~—1.5 mm. across, early naked, pulveru- 
lent, cinnamon-brown, rupttred epidermis noticeable ; urediniospores variable, broadly ellip- 
soid, obovoid, or cuneate, 19-26 by 22-32 u; wall light or dark cinnamon-brown, variable in 
thickness, 1.5-3 n, moderately and strongly echinulate, markings often deciduous, the pores 
2, equatorial or on some hosts subequatorial, occasionally 3, with one at apex, often with a 
smooth area around pores. 
III. Telia chiefly epiphyllous, becoming amphigenous and caulicolous, scattered or oc- 
casionally confluent, round, small, 0.5-1.5 mam. across on leaves, elongate to 1 em. and causing 
fusiform hypertrophy when caulicolous, early naked, becoming pulverulent, blackish, ruptured 
epidermis noticeable; teliospores subgloboid, broadly ellipsoid, or oblong, 24-32 by 36-48 yu, 
rounded above and below, slightly or not at all constricted at septum; wall dark chestnut- 
brown, 3-5 » thick, thickened at apex to 10 » by a broad lighter colored umbo, often thickened 
in a similar manner over pore of lower cell, smooth; pedicel colorless, 5-7 » in diameter near 
spore, tapering below, usually persistent, once to thrice length of spore. 
On CaRDUACEAE: 
Verbesina dissita A. Gray, Lower California. 
Verbesina longipes Hemsl., San Luis Potosi. 
Verbesina montanoifolia Rob. & Greenm., Michoacan. 
Verbesina perymenioides Schultz-Bip., Oaxaca; Guatemala. 
Verbesina Rothrockii Rob. & Greenm., Coahuila. 
Verbesina trilobaia Rob. & Greenm., Oaxaca. 
Verbesina virgata Cav., Mexico (state). 
Verbesina sp., California. 
Viguiera buddleiaeformis Benth. & Hook., Mexico (state), Michoacan. 
Viguiera excelsa Benth. & Hook., Mexico (state). 
Viguiera helianthoides H.B.K., Te exas; Aguascalientes, Hidalgo, Pueblo; Cuba. 
Viguiera sylvatica Klatt, Costa Rica. 
Viguiera tenuis A. Gray, Jalisco. 
Ximenesia encelioides Cav., Texas. 
TYPE LOCALITY: Mexico, on Viguiera helianthoides. 
DistTRiIBvUTION: Southern part of Texas and of California to Guatemala, and in Cuba. 
Exsiccati: Barth. Fungi Columb. 3452, 3831, 4560, 4949; Barth. N. Am. Ured. 15, 118, 119, 
524, 1215, 1323, 1326, 1516; Ellis & Ev. Fungi Columb. 1638; Sydow, Ured. 1514, 1705, 2057, 2540. 
259. Dicaeoma senecionicola (Arth.) Arthur & Jackson. 
Puccinia senecionicola Arth. Bot. Gaz. 40: 199. 1905. 
O. Pycnia epiphyllous, crowded in spots 1-5 mm. in diameter, noticeable, chestnut- 
brown, globoid or flattened-globoid, 112-175 u wide by 96-128 uw high; ostiolar filaments up to 
75 uw long, usually agglutinated into a column. 
I. Aecia hypophyllous, rather loosely grouped upon spots 2-5 mm. in diameter, flattened- 
hemispheric, large, 0.5-1 mm. in diameter; peridium white, the margin incurved, fragile, 
covered more or less by the overarching epidermis; peridial cells oblong, 19-23 by 39-55 y, 
abutted, the walls 3-5 » thick, the outer smooth, the inner closely and noticeably verrucose; 
aeciospores irregularly globoid or ellipsoid, 22-30 by 26-36 4; wall colorless, thick, 2-3.5 yu, 
closely and coarsely verrucose. 
+ II. Uredinia amphigenous, scattered or in small groups, round, 0.2-1 mm. in diameter, 
somewhat tardily naked, pulverulent, cinnamon-brown, ruptured epidermis noticeable; 
urediniospores globoid or ellipsoid, 21-27 by 26-35 1; wall cinnamon- or chestnut-brown, 
1.5-3 » thick, usually thinner about the pores than above, sometimes 1 », moderately and 
strongly echinulate, the pores 2, opposite and equatorial or occasionally superequatorial. 
Il. Telia hypophyllous, at first circinating about the uredinia, finally scattered, round, 
0.1-0.8 mm. in diameter, long covered by the epidermis, bullate, compact, grayish-brown, 
ruptured epidermis finally conspicuous; teliospores ellipsoid or oblong-clavate, 18-30 by 37- 
64», rounded or obtuse above, more or less narrowed below, slightly, constricted at septum; 
wall cinnamon- or chestnut-brown, 1.5—3 » thick, usually with a semihyaline covering at apex, 
3-12 p, smooth; pedicel light cinnamon-brown, up to length of spore. 
On CaRDUACEAE: 
Cacalia amplifolia DC., Oaxaca. 
Cacalia ampullacea Greenman, Hidalgo. 
