420 NORTH AMERICAN FLORA [VoLUME 7 
232. *Dicaeoma Becki (Mayor) Arthur & Jackson. 
Puccinia Becki Mayor, Mém. Soc. Neuch. Sci. Nat. 5: 509, 1913. 
O. Pycnia epiphyllous, few, gregarious on yellowish somewhat hypertrophied spots, 
0.5-1 mm. across, frequently extending along veins, conspicuous, orange-yellow fading to 
blackish, globoid or flask-shaped, 112-120 by 125-130 y; ostiolar filaments 50 » long. 
I. Aecia hypophyllous, few or solitary, in groups opposite the pyenia, cylindric; peridium 
white, membranous, lacerate; peridial cells seen only in face view, irregularly polyhedral, 16-23 
by 26-32 yp, the wall colorless, thin, 1.5-2 4, prominently verrucose-rugose; aeciospores globoid or 
ellipsoid, somewhat irregular, 16-22 by 23-34 »; wall colorless, 2 » thick, closely and promi- 
nently verrucose with low warts often arranged in longitudinal lines, especially near either end. 
II. Uredinia amphigenous, chiefly hypophyllous, scattered, small, 0.2-0.5 mm. across, 
round, early naked, somewhat pulverulent, cinnamon-brown, ruptured epidermis not con- 
spicuous; urediniospores globoid or broadly ellipsoid, 18-22 by 22-24 yu; wall pale cinnamon- 
brown, about 2 « thick, moderately echinulate, the pores obscure. 
III. Telia chiefly hypophyllous, scattered, small, 0.2-0.5 mm. across, round, early naked, 
compact, pulvinate, germinating at maturity, chestnut-brown, ruptured epidermis not con- 
spicuous; teliospores cylindric or fusiform, 13-19 by 58-90 4; wall cinnamon-brown, uniformly 
1-1.5 » thick, smooth; pedicel colorless, fragile, short, up to 40 ¢ long. 
On CARDUACEAE: 
Vernonia divaricata Sw., Jamaica. 
Tyres LocaLtity: Near Bogota, Dep. Cundinamarca, Colombia, on Vernonia Cotoneaster. 
DISTRIBUTION: Jamaica; also in South America. 
ILLUSTRATION: Mém. Soc. Neuch. Sci. Nat. 5: 509, f. 36. 
233. Dicaeoma erraticum (Jackson & Holway) Arthur 
& Jackson. 
Dietelia Vernoniae Arth. Bot. Gaz. 40: 198. 1905. Not Dicaeoma Vernoniae Kuntze, 1898. 
Endophyllum Vernoniae Arth. N. Am. Flora 7: 126. 1907. 
Puccinia erratica Jackson & Holway; H. S. Jackson, Bot. Gaz. 65: 294, 1918. 
QO. Pycnia epiphyllous, numerous, in crowded groups 1 mm. across, in the center of 
yellowish spots 0.5-1 cm. in diameter, conspicuous, subepidermal, orange becoming blackish, 
globose or flask-shaped, 120-145 by 145-160 y; ostiolar filaments not extruded. 
I. Aecia hypophyllous, few or solitary, crowded on the under surface of yellowish spots 
opposite the pycnia or occasionally more or less scattered, bullate, 0.2-0.5 mm. across; peridium 
wauting; aeciospores somewhat irregularly ellipsoid, oblong or pyriform, 23-28 by 32-38 u, 
somewhat flattened, the wall colorless, 2-3 «4 thick, prominently and closely verrucose-rugose, 
with tendency toward an arrangement in lines and becoming united to form ridges at one end 
of the spore, tubercles often deciduous. 
II. Uredinia hypophyllous, few, scattered, roundish, small, 0.1-0.3 mm. across, rather 
tardily naked, pulverulent, cinnamon-brown, ruptured epidermis conspicuous; urediniospores 
globoid or broadly obovate, 23-28 by 29-34; wall cinnamon-brown, 1-1.5 u, moderately 
echinulate, the pores 3, approximately equatorial. 
III. Telia hy pophyllous, ntrmerous, scattered or gregarious, round, small, 0.2-0.5 mm. 
across, early naked, pulvinate, chestnut-brown, ruptured epidermis noticeable; teliospores 
cylindric-terete or fusiform, 16-22 by 56-80 », narrowed at both ends, obtuse at apex, not thick- 
ened, slightly constricted at septum; wall cinnamon-brown, thin, 1-1.5 », smooth; pedicel 
colorless, fragile, equaling spore in length or usually shorter. 
On CaRDUACEAE: 
Vernonia Schiedeana Less., Oaxaca, Veracruz; Guatemala. 
Type Locality: Jalapa, Mexico, on ‘‘ Vernonia Deppeana,” now determined as V. Schiedeana. 
DISTRIBUTION: Southern Mexico and Guatemala. 
234. Dicaeoma fraternum (H. S. Jackson) Arthur 
& Jackson. 
Puccinia fraterna H. S. Jackson, Bot. Gaz. 65: 297. 1918. 
O. Pycnia epiphyllous, few, gregarious, noticeable, blackish, globoid, 110-120 » in diam- 
eter; ostiolar filaments not protruding. 
* Species of Dicacoma on Carduaceae in collaboration with HerRBEeRT SPENCER JACKSON. 
