Part 5, 1920] AECIDIACEAE 353 
122. Dicaeoma atrofuscum (Dudley & Thompson) Arth. Résult. 
Sci. Congr. Bot. Vienne 343. 1906. 
Uromyces atrofuscus Dudley & Thompson, Jour. Myc. 10:55. 1904. 
Puccinia atrofusca Holway, Jour. Myc. 10: 228. 1904. 
O and I. Pycnia and aecia unknown. 
II. Uredinia of the usual sort amphigenous, scattered, oval or oblong, 0.2-0.5 mm. long, 
early naked, applanate, cinnamon-brown, ruptured epidermis noticeable; urediniospores 
broadly ellipsoid, 16-21 by 21-26 4; wall cinnamon-brown, 1.5-2 uw thick, rather closely echi- 
nulate, the pores 2, opposite. 
Uredinia of the modified sort (amphisori) amphigenous, oval or oblong, 0.5-1 mm. long, 
early naked, pulvinate, slightly pulverulent, dark chocolate-brown, ruptured epidermis notice- 
able; urediniospores of the modified sort (amphispores) broadly ellipsoid or obovoid, 17-24 by 
23-32 »; wall chestnut-brown, 2.5~3.5 » thick, somewhat thicker above, 4~7 u, rather sparsely 
but prominently verrucose-echinulate especially above, the pores 2, approximately equatorial. 
III. Telia not seen; teliospores few in the uredinia, narrowly obovate-ellipsoid or clavate- 
oblong, 16-22 by 30-43 yu, rounded or obtuse at each end, slightly constricted at septum; wall 
chestnut-brown, 1.5-2 u thick, much thicker above, 5~7 », smooth; pedicel slightly tinted, 
about length of spore. , 
On CYPERACEAE: 
Carex Douglasii Boott, California, Colorado, Montana, Nevada, New Mexico, Oregon, 
Washington, Wyoming; Alberta. 
Carex nigricans C. Meyer, Utah. 
Carex praegracilis W. Boott (C. marcida Boott, C. usta L. H. Bailey), California, Colorado. 
TYPE LocaLIty: Palmers, Mariposa County, California, on Carex Douglasii. 
Fe fee Southern Alberta to Washington, and southward to New Mexico and southern 
aliiornia. 
Exsiccati: Barth. Fungi Columb. 2676, 3742; Barth. N. Am. Ured. 820, 1027, 1934, 1935; 
Clements, Crypt. Form. Colo. 547. 
123. Dicaeoma macrosporum (Peck) Arthur & Kern. 
Aecidium macrosporum Peck, Ann. Rep. N. Y. State Mus. 23:61. 1873. 
Puccinia macrospora Arth. Mycologia 1: 244. 1909. 
O. Pycnia epiphyllous, gregarious, few, in groups on slightly discolored spots, not con- 
spicuous, honey-yellow, flattened-globoid, 128-160 » in diameter by 80-100 w high; ostiolar 
filaments rather short. 
I. Aecia hypophyllous, gregarious, chiefly in annular groups 1.5-5 mm. across, rather 
short, 0.1-0.2 mm. in diameter; peridium colorless, the margin erose; peridial cells linear- 
rhomboid, 32-42 » long, rather thin, the outer wall smooth, the inner wall somewhat thicker, 
moderately verrucose; aeciospores globoid, very large, 32-42 by 37-51 u: wall colorless, moder- 
ately thick, 1.5-2.5 u, thicker above, 5-10 w, rather coarsely verrucose. 
ON SMILACACEAE: 
Smilax glauca Walt., New Jersey. 
Smilax hispida Muhl., Kansas, New Jersey. 
Smilax rotundifolia L., Delaware, New Jersey, New York. 
JI. Uredinia amphigenous, scattered or in longitudinal series, oblong, 0.5—1 mm. long, 
long covered by the epidermis; urediniospores obovate or narrowly ellipsoid, rather irregular, 
very large, 26-37 by 35-61 u, often narrowed below to a thickened hilum; wall golden-yellow, 
evenly thick, 2.5-3.5 u, echinulate with prominent points 3-4 » apart, the pores obscure, 2, 
or sometimes 3, equatorial. 
III. Telia chiefly hypophyllous, scattered or in longitudinal series, oblong or linear, 
0.5-1.5 » long, finally naked, pulvinate, chocolate-brown, ruptured epidermis noticeable; 
teliospores clavate, 16-23 by 61-67 u, usually rounded or obtuse above, narrowed below, usually 
slightly constricted at septum; wall pale cinnamon-brown, paler below, 1.5-2.5 » thick, much 
thicker at apex, 9-16 ; pedicel colorless, one half to once length of spore. 
On CYPERACEAE: 
Carex comosa Boott, Delaware. 
Carex vestita Willd., New Jersey. 
Carex sp., New Jersey. 
‘TypR LOCALITY: Riverhead, New York, on Smilax rotundifolia. . . 
DISTRIBUTION: Limited area near the coast from Long Island to Delaware, with a single col- 
lection of aecia from Kansas. 
