Part 5, 1920] AECIDIACEAE 385 
167. Dicaeoma parcum Arthur. 
Puccinia parca Arth. Bull. Torrey Club 46:117. 1919. 
Oand I. Pycnia and aecia unknown. 
II. Uredinia hypophyllous, scattered or irregularly grouped, roundish, 0.3-0.6 mm. across, 
early naked, brownish-yellow, pulverulent, ruptured epidermis noticeable; urediniospores 
narrowly ellipsoid or obovoid, 13-16 by 19-26 2 ; wall brownish- or light-yellow, very thin, 1 
or less, moderately and inconspicuously echinulate, the pores 2-4, equatorial or superequatorial. 
Ill. Telia hypophyllous, scattered or irregularly grouped, roundish, 0.3-1 mm. across, 
early naked, dark cinnamon-brown, pulverulent, ruptured epidermis inconspicuous; telio- 
spores ellipsoid or oblong, 15-19 by 29-42 u; wall cinnamon-brown, rather thin, 1-2 u, thickened 
into a hemispheric hyaline papilla over the pores, 4-5 y, smooth; pedicel colorless, one half 
length of spore or less, fragile. 
ON POLYGONACEAE: 
Bilderdykia scandens (I,.) Greene (Polygonum scandens l,., Tiniaria scandens Small), New 
Jersey, New York, North Carolina. : 
TYPE LOCALITY: Stelton, New Jersey, on Tiniaria scandens. 
Disrripution: Atlantic coast from Long Island to western North Carolina. 
Iutusrrations: Holway, N. Am. Ured. 1: pl. 13, f. 56a, b. 
Exsiccatr: Seym. & Earle, Econ. Fungi 367. 
168. Dicaeoma Polygoni-alpini (Cruchet & Mayor) Arthur. 
Puccinia Polygoni-alpini Cruchet & Mayor; Cruchet, Bull. Herb. Boiss. II. 8: 245. 1908. 
O and I. Pycnia and aecia unknown. 
II. Uredinia hypophyllous, scattered, round, 0.3-1 mm. in diameter, early naked, pul- 
verulent, yellow or brownish-yellow, ruptured epidermis conspicuous; urediniospores globoid 
or ellipsoid, 18-24 by 23-27 yw; wall yellowish, rather thick, 1.5~2 yu, finely and closely echinu- 
late, the pores rather indistinct, about 4-6, scattered, sometimes appearing equatorial. 
III. Telia amphigenous, mostly hypophyllous, scattered or in loose, circinating groups 
3-5 mm. across, round, 0.3-1.5 mm. in diameter, early naked, pulverulent, dark cinnamon- 
brown, ruptured epidermis conspicuous; teliospores ellipsoid or angularly ellipsoid, 16-21 
by 22-32 », rounded above and below, slightly constricted at septum; wall dark cinnamon- 
brown, thin, 1-1.5 », thickened into a small hyaline umbo over the pores, 1.5-2 y, closely 
verrucose in irregular, longitudinal lines 5—7 » apart; pedicel colorless, fragile. 
ON POLYGONACEAE: 
a AS phytolaccaefolium (Meissn.) Small (Polygonum alpinum Am, Auth.), Idaho, 
gon. 
TYPE LOCALITY: Valais mountains, Gries Pass, northern Italy, on Polygonum alpinum. 
DistRiBUTION: Alpine stations in Idaho ‘and Oregon; also in Asia and Europe. 
169. Dicaeoma Acetosae (Schum.) Kuntze, Rev. 
Gen. 33: 467. 1898. 
Uredo Acetosae Schum. Enum, Pl. Saell. 2: 231. 1803. 
Puccinia Acetosae Kérn. Hedwigia 15: 184. 1876. 
O and I. Pycnia and aecia unknown. 
Il. Uredinia amphigenous and caulicolous, scattered, round, small, 0.3-1 mm. across, 
early naked, pulverulent, cinnamon-brown, ruptured epidermis noticeable; urediniospores 
globoid or ellipsoid, 20-25 by 23-30 »; wall light chestnut-brown, moderately thick, 1.5-2.5 y, 
sparsely and moderately echinulate, the pores 2, superequatorial. 
III. Telia amphigenous and caulicolous, scattered, rounded or oblong on the stems, small, 
0.3-1 mm. across, pulverulent, chocolate-brown, ruptured epidermis noticeable; teliospores 
ellipsoid or oblong, 19-26 by 30-46 », rounded at both ends, constricted at septum; wall dark 
chestnut-brown, thick, 2-3 4, sometimes with a slight hyaline thickening at apex, 3-5 z, 
smooth; pedicel hyaline, slender, deciduous, sometimes as long as spore. 
On POLYGONACEAE: 7 : : 
Rumex Acetoselle J,., Alabama, California, Florida, Indiana, Massachusetts, New York, 
Oregon. 
Rumex hastatulus Baldw., Florida, Massachusetts, South Carolina. 
TypH LOCALITY: Island of Zealand, Denmark, on Rumex Acetosa. 
