Part 4, 1920] AECIDIACKAE 291 
ILLustRations: Bull. Lab. Nat. Hist. Univ. Iowa 4: pl. 5, f. 23a-d; Ann. Rep.N.Y. State Mus. 
25: pl. 2, f. 36a. 
Exsiccatr: Arth. & Holway, Ured. Exs. Ic. 23a-d; Barth. Fungi Columb. 4957, 4958; Barth. 
N. Am. Ured. 339, 1239, 1753, 1841, 2243; Carleton, Ured. Am. 37; Ellis & Ev. Fungi Columb. 
2054, 2148; Ellis, N. Am. Fungi 1029; Kellerm. Ohio Fungi 56; Kellerm. & Swingle, Kan. Fungi 15; 
Rab.-Wint. Fungi Eur. 3616; Seym. & Earle, Econ. Fungi 58a, b, c; Sydow, Ured. 1973. 
26. Dicaeoma Pammelii (Trel.) Arth. Proc. Ind. Acad. Sci. 1903: 
149. 1904. 
Aecidium Pammelii Trel. Fungi Wis. 32. 1884; Trans. Wis. Acad. 6: 136. 1885. 
Puccinia Panici Dietel, Erythea 3: 80. 1895. 
Puccinia Panici robusta Barth.; Ellis & Ev. Fungi Columb. 1769. 1903. 
Puccinia Pammelii Arth. Jour. Myc. 11: 56. 1905. 
O. Pycnia chiefly epiphyllous, in small circular groups, crowded, conspicuous, honey- 
yellow, globose in vertical section, 120-155 w in diameter; ostiolar filaments very short. 
I. Aecia hypophyllous, in circular groups, 2~10 mm. in diameter on discolored areas, low- 
cupulate, small, 0.2-0.3 mm. in diameter; peridium whitish, somewhat evanescent, the margin 
irregularly lacerate and slightly recurved; peridial cells oblong, 13-19 by 21-35 uw, abutted or 
slightly imbricate, the outer wall thick, 7-10 4, smooth, transversely striate, the inner wall 
thinner, 2-4 uw, verrucose; aeciospores globoid or ellipsoid, 16-23 by 21-32 »; wall colorless or 
pale-yellow, 2-3 « thick, minutely and evenly verrucose. 
On EUPHORBIACEAE: 
Dichrophyllum marginatum (Pursh) Ki. & Garcke (Euphorbia marginata Pursh), Colorado, 
Kansas, Nebraska, Oklahoma, Texas. 
Tithymalopsis corollata (L.) Kl. & Garcke (Euphorbia corollata L.), Alabama, Illinois, In- 
diana, Iowa, Minnesota, Missouri, Nebraska, Wisconsin. 
Tithymalopsis Ipecacuanhae (1..) Small, New Jersey. 
Zygophyllidium hexagonum (Nutt.) Small (Euphorbia hexagona Nutt.), Nebraska. 
Il. Uredinia epiphyllous, scattered, oblong, small, 0.5 mm. long, early naked, cinnamon- 
brown, pulverulent, ruptured epidermis evident; urediniospores broadly ellipsoid, 19-27 by 
21-30 4; wall golden- or light cinnamon-brown, 1.5-2 » thick, finely and closely echinulate, 
the pores 3-4, approximately equatorial, inconspicuous. 
III. Telia epiphyllous or sometimes amphigenous, scattered or sometimes crowded and 
forming lines, oblong, small, 0.5-2 mm. long, early naked, compact, dark chocolate-brown, 
conspicuous, ruptured epidermis evident; teliospores ellipsoid or oblong, 16-24 by 27-45 y, 
rounded, obtuse or acttte above, narrowed below, slightly or not constricted at septum; wall 
smooth, dark cinnamon- or chestnut-brown above, paler below, 1~1.5 4 thick, thicker above, 
5-7 w; pedicel colorless or slightly tinted, one to one and a half times length of spore. 
This species is morphologically identical with Nagredo gramimicola except in the presence 
of two-celled teliospores, and should eventually be united with it under one name. 
On POACEAE: . ae 
Panicum virgatum L., Alabama, Colorado, Delaware, Indiana, Jowa, Kansas, Mississippi, 
Nebraska, New Jersey, Ohio, Pennsylvania, South Dakota, Texas, West Virginia, 
Wisconsin. 
Panicum virgatum cubense Griseb., New Jersey. 
TPE LOCALITY: LaCrosse, Wisconsin, on Euphorbia corollata. . 
DIstRIBUTION: From the Atlantic coast westward to the Rocky mountains, and southward to 
Mississippi and Alabama, . . 
ILLUSTRATIONS: Bull. Lab. Nat. Hist. Univ. Iowa 4: pl. 4, f. 20a-c. . 
Exsiecati: Arth. & Holway, Ured. Exs. Ic. 20a-c; Barth. Fungi Columb. 3668, 3855; Barth. 
N. Am. Ured. 250, 251, 757, 1064; Ellis & Ev. Fungi Columb. 264, 1389, 1706, 1769; Ellis, N. Am. 
Fungi 1427; Ellis & Ev. N. Am. Fungi 2217, 3048; Rab.-Paz. Fungi Eur. 4140; Roum. Fungi Sel. 
4413; Seym. & Earle, Econ. Fungi 544; Sydow, Ured. 1178, 1249. 
27. Dicaeoma atrum (Dietel & Holway) Arth. Résult. Sci. Congr. 
Bot. Vienne 344. 1906. 
Puccinia otra Dietel & Holway; Holway, Bot. Gaz. 24:29. 1897, 
OandI. Pycnia and aecia unknown. 
II. Uredinia epiphyllous, scattered or sometimes confluent, oblong or elliptic, 0.5-2 mm. 
long, early naked, pulverulent, cinnamon-brown, ruptured epidermis apparent; urediniospores 
broadly ellipsoid or obovoid, 21-29 by 26-32 u; wall 1.5~—2 w thick, brownish-yellow or light 
cinnamon-brown, very minutely and closely verrucose, the pores 4, occasionally 5, equatorial. 
