154 ARTHUR: NEW SPECIES OF UREDINEAE 
‘I. Aecia hypophyllous, numerous, opposite the pycnia, in well- 
defined groups 0.3-0.6 mm. across, on roseate or yellowish spots 
I0-I5 mm. across, cupulate; peridium usually erect, the margin 
erose or lacerate; peridial cells easily separating, rhomboid, little 
or no longer than broad, 19-26 by 26-37 u, the outer wall 8-10 p 
thick, faintly striate, the inner wall 3-6 u thick, moderately ver- 
rucose; aeciospores globoid, 13-18 by 16-19 y; wall nearly or quite 
colorless, thin, I-1.5 4, very minutely verrucose, appearing smooth 
when wet. 
On Perezia sp., Barranca, Mexico, July 25, 1893, C. G. Pringle, 
communicated by W. G. Farlow. A distinctive species, and 
doubtless heteroecious. 
Aecidium steviicola sp. nov. 
O. Pycnia amphigenous, numerous, in loose groups, punctate, 
honey-yellow becoming brown, noticeable, subepidermal. 
I. Aecia hypophyllous, in loose groups surrounding the pycnia 
on yellowish spots 10-15 mm. across, cupulate, the margin some- 
what reverted, erose or lacerate; aeciospores globoid, large, 24-32 
by 30-40; wall colorless, rather thin, about 1.5 uw, considerably 
thickened above, 6-9 4, minutely and closely verrucose. 
On Stevia sp., Popo Park, Federal District of Mexico, August 
4-8, 1910, A. S. Hitchcock. 
This is doubtless a heteroecious form. It much resembles 
A. roseum Diet. & Holw., which occurs in Mexico on species of 
Stevia, but more abundantly on Eupatorium, and which is be- 
lieved to be the aecial stage of a grass rust, probably A egopogon, 
but the spores are nearly half as much longer than in that form, 
although in other respects there is close similarity. 
Aecidium Keerliae sp. nov. 
O. Pycnia amphigenous, in close groups I-2 mm. across, 
honey-yellow becoming brown, punctiform, noticeable, subepi- 
dermal. 
I. Aecia hypophyllous, in groups 3-8 mm. across, on somewhat 
larger, yellowish spots, cupulate, low; peridium slightly recurved, 
erose or lacerate; aeciospores globoid or ellipsoid, small, 12-18 
by 15-20; wall nearly or quite colorless, thin, 1 #, much thicker 
above, 3-6 y, finely and closely verrucose. 
On Keerlia mexicana A. Gray, Guadalajara, Mexico, July 14, 
