Arthur: Cultures of Uredineae in 1908 247 



found hundreds of cases to substantiate it — I wish you would try 

 it," a sowing was accordingly made April 30 on Mahonia Aqui- 

 folium. Abundance of pycnia appeared May 14, and aecia May 

 24. Another sowing was made June 2 on Berberis vulgaris, but 

 gave no infection. 



Upon examination of the available collections of aecia on Ma- 

 honia, which had not been given careful study before, it was dis- 

 covered that they differed in a characteristic way from those on 

 Berberis. They are smaller, do not produce a thickening of the 

 leaf, and cause a rounded area of the leaf on which each group is 

 seated to die early, turning brown and dry. From our inquiry 

 it seems probable that no aecia on Mahonia belonging to Puccinia 

 poculiformis have yet been found in America, although they have 

 been so cited, but that they all should go under the present species, 

 a description of which follows. 



Puccinia Koeleriae sp. nov. 



0. Pycnia chiefly epiphyllous, numerous, rather loosely arranged 

 in groups 0.5-2 mm. across, on discolored spots, punctiform, not 

 conspicuous, subepidermal, honey-yellow becoming blackish, in 

 vertical section lenticular, 80-ioOft in diameter by 45-65/x high. 



1. Aecia hypophyllous, numerous, usually crowded in groups 

 1-3 mm. or more across, on discolored spots 1-7 mm. across, 

 which finally die and turn blackish-brown, short cylindrical, 0.4- 

 0.7 mm. high by 0.1-0.2 mm. in diameter; peridium colorless, 

 cells rhomboidal in radial section, outer wall rather thick, 5-7^, 

 transversely striate, inner wall medium thin, 1-3/x, verrucose; 

 aeciospores globoid, 13-20 by 18-26/x, wall colorless, rather thin, 

 1-1.5/x, evenly and finely verrucose. 



On Mahonia Aquifolium (Pursh) Nutt. {Berberis Aquifolium 

 Pursh, B. repens Lindl.), Ouray, Colo., July 26, 1897, C. L. Shear, 

 July 2, 1907, E. Bethel; Victor, Idaho, July 10, 1901, E. D. Mer- 

 rill & E. N. Wilcox; Wild Horse Island, Mont., Aug. 13, 1908, 

 M. E. Jones 7718; Yellow Bay, Mont., Aug. 10, 1908, M. E. Jones 

 77?3- 



II. Uredinia amphigenous, in groups on discolored spots, oblong 

 or linear, 0.1-0.2 mm. wide by 0.5-1.5 mm. long, soon naked, pul- 

 verulent, cinnamon-brown, ruptured epidermis conspicuous ; para- 

 physes numerous, capitate or clavate-capitate, 10-16 by 42-65^; 

 urediniospores broadly ellipsoid, 19-26 by 23-34/x ; wall cinnamon- 

 brown, medium thick, 2-2. 5/x, rather closely echinulate-verrucose ; 

 pores 4-6, scattered. 



III. Telia hypophyllous, scattered, oblong or linear, about 0.1 



