ARTHUR: NEW SPECIES OF UREDINEAE 117 
Puccinia parca sp. nov. 
II. Uredinia hypophyllous, scattered or irregularly grouped, 
roundish, 0.3-0.6 mm. across, brownish-yellow, pulverulent; 
urediniospores narrowly ellipsoid or obovoid, 13-16 by 19-26 y; 
wall brownish- or light-yellow, very thin, 1 u or less, moderately 
and inconspicuously echinulate, the pores indistinct, 2-4, equa- 
torial or superequatorial. . 
II. Telia similar but slightly larger than the uredinia, dark 
cinnamon-brown, pulverulent; teliospores ellipsoid or oblong, 
15-19 by 29-42; wall cinnamon-brown, rather thin, 1-2 4, 
thickened into a hemispherical hyaline papilla over the pores, 
4-5 u, smooth; pedicel colorless, one half length of spore or less, 
fragile. 
On Tiniaria scandens (L.) Small (Polygonum scandens L.), 
Flatbush, Long Island, New York, October 5, 1889, II, III, 
J. L. Zabriskie 703; Stelton, New Jersey, September 7, 1892, 
II, III, Byron D. Halsted (Seym. & Earle, Econ. Fungi 367, 
type); Laurel Springs, northwestern North Carolina, September 
20, 1904, II, Ill, H. H. Hume 278. As long ago as October, 
1905, Professor Holway called the attention of the writer to 
the peculiarities of the rust issued by Seymour & Earle in their 
Economic Fungi under the name of P. mammillata. Professor 
Holway pointed out that that species has rough spores and of a 
different shape from this material. He thought it might be a new 
species, but later in his North American Uredineae (1: 40) placed 
it doubtfully under P. septentrionalis Juel. P. septentrionalis is a 
boreal species on Bistorta viviparum, having its aecia on Thalic- 
trum alpinum, and in America has been taken in Alaska and New- 
foundland. The rust in question agrees with P. septentrionalis 
in the character of its teliospores, as Professor Holway pointed 
out in detail, but differs from it in having slightly narrower uredin- 
iospores, with thinner walls, of a lighter and more yellowish color. 
The species is markedly distinct from P. Polygoni A. & S., the 
common rust on the same and related hosts, both in the teliospores 
and urediniospores. The pores of the urediniospores are difficult 
to make out, but are usually three and approximately equatorial, 
while in the more common P. Polygoni they are distinct and two in 
the upper part of the spore. 
