Part 4, 1920] AECIDIACEAE 285 
III. Telia amphigenous, scattered or somewhat gregarious, oblong, 1-3 mm. long, tardily 
naked, compact, dark chocolate-brown, ruptured epidermis conspicuous; teliospores ellipsoid 
or oblong, 23-32 by 40-55 p, rounded or obtuse at apex, usually narrowed below, slightly or 
not constricted at septum; wall uniformly colored throughout, dark chestnut- or chocolate- 
brown, smooth, rather thick, 2-3 4, moderately thickened at apex, 4-7 u; pedicel colorless, 
persistent, once to twice length of spore. 
On PoAackEaE: 
Holcus halepensis L. (Andropogon halepensis Brot., Sorghum halepense Pers.), Alabama, 
ow Florida, Louisiana, South Carolina, Texas; Veracruz, Yucatan; Cuba; 
amaica. 
Holcus Sorghum 1. (Andropogon Sorghum Brot., Sorghum vulgare Pers., S. Dora Griseb.), 
California, Florida, Oklahoma, Texas; Guerrero; Costa Rica; Bermuda; Cuba; Porto 
co. 
Holcus Sorghum sudanensis (Piper) Hitche., Porto Rico. 
TYPE LocaLity: India, on Sorghum vulgare. 
Distr1BuTIoN: South Carolina to Texas and southern California, and southward through the 
WestIndies and Central America ; also in South America, Europe, Asia, northern Africa, and Hawaii. 
Exsiccati: Barth. Fungi Columb. 2464, 2673, 4670; Barth. N. Am. Ured. 963, 1072, 1666, 
1773; Ellis & Ev. Fungi Columb. 1656; Ellis & Ev. N. Am. Fungi 2416; Rav. Fungi Am. 277; Sydow, 
Ured. 2328. 
13. Dicaeoma Aegopogonis (Arth. & Holway) Arthur & Fromme. 
Puccinia Aegopogonis Arth. & Holway; Arth. Am. Jour. Bot. 5: 467. 1918. 
O. Pycnia epiphyllous, numerous, usually crowded in irregular groups, on yellow spots 
with roseate border, moderately conspicuous, golden-yellow, becoming brownish, globoid or 
flask-shaped in cross section, 100-150 w in diameter; ostiolar filaments present, compact. 
I. Aecia hypophyllous, irregularly crowded in more or less orbicular groups, wp to 2 mm. 
across, cuptlate to short-cylindric, 0.1-0.2 mm. in diarheter; peridium light-yellow, margin 
somewhat recurved, erose; peridial cells rhomboidal, 18-24 by 29-38 u, usually seen in face 
view, considerably overlapping, the outer wall colorless, smooth, transversely striate, 7 » 
thick, the inner wall thinner, 2-4 u, finely and closely verrucose; aeciospores globoid or ellip- 
soid, angular, 15-26 by 19-36 u; wall colorless, 1-2 » thick, thickened above up to 7 y, closely 
and finely verrucose. 
On CaARDUACEAE: 
Eupatorium Mairetianum DC., Guatemala. 
II. Uredinia hypophyllous, scattered, oblong-linear, small, 0.2-0.5 mm. long, cinnamon- 
brown, pulverulent, early naked, ruptured epidermis apparent; urediniospores globoid or 
“broadly ellipsoid, 21-25 by 23-294; wall golden- or light cinnamon-brown, thin, 1-1.5 y, 
finely and closely echinulate, the pores 6~8, scattered. 
III. Telia hypophyllous, like the uredinia in size and distribution, chocolate-brown, 
early naked; teliospores broadly ellipsoid, 19-22 by 24-28, rounded above and below, 
slightly or not constricted at.septum, which is often oblique; wall chestnut-brown, moderately 
thin, about 1.5 », darker and slightly thicker at apex, 3-5 4, smooth; pedicel yellowish or color- 
less, once to twice length of spore. 
This species is morphologically identical in all essential characters with Nigredo Aegopo- 
gonis (Dietel & Holway) Arth., except in the possession of two-celled teliospores. The uredin- 
iospores, however, generally range slightly larger. The two forms should eventually be united 
under one name. 
On PoackaE: 
Aegopogon cenchroides Humb, & Bonpl., Guatemala. 
Aegopogon tenellus (Cav.) ‘Trin. (A. unisetus R. & §.), Guatemala. . 
TypE LOCALITY: San Rafael, Department of Guatemala, Guatemala, on Aegopogon cenchroides. 
DISTRIBUTION: Guatemala. 
14. Dicaeoma Arundinellae (Arth. & Holway) Arthur & Fromme. 
Uredo Arundinellae Arth. & Holway; Arth. Mycologia 10: 148. 1918. 
O and I. Pycnia and aecia unknown. 
II. Uredinia hypophyllous, scattered, oval or oblong, minute, 0.1-0.3 mm. long, early 
naked, pulverulent, cinnamon-brown, ruptured epidermis evident; urediniospores broadly 
