Arthur and Holway : VIOLET RUSTS OF NORTH AMERICA. 639 



20-25 p by 35-40;* for the teleutospores. The name has been 

 very little used by American or other botanists. The assign- 

 ment of the name to a place under the wholly distinct Puccinia 

 Fergussoni, as done by De Toni in the seventh volume of 

 Saccardo's Sylloge fungorum, was far from being a shrewd 

 guess as to its relationship. It is even more inexplicable how 

 Dietel could have fancied a resemblance to Puccinia Fergussoni 

 in the type material of his Puccinia dcnsa. His material of the 

 latter species was collected in 1895 by W. N. Suksdorf in the 

 State of Washington. It was on Viola glabella, and yielded 

 only teleutospores. The characters which he drew up for the 

 proposed new species agree perfectly with those of large-spored 

 forms of Puccinia Viola. Beside the type collection we have 

 examined material on the same host from other localities in the 

 same State, and secured by the same collector. This ample 

 material includes all three spore stages, and leaves no doubt of 

 the identity of P. densa Diet, with P. Viola. 



All the hosts of the specimens cited under Viola Montanensis, 

 and part of those under V. adunca, have been determined or 

 verified by Dr. P. A. Rydberg of the New York Botanical Garden. 



An error in the thirteenth volume of Saccardo's Sylloge fun- 

 gorum, page 1313, should be pointed out here. Puccinia 

 Maria- Wilsoni Clint, is said to occur on Viola cucullata Ait. 

 and V. delphinifolia Nutt. The error is due to a confusion of 

 names. ^Ecidium Maria- Wilsoni Peck is found on these 

 hosts but Puccinia Maria- Wilsoni Clinton is only found on 

 Claytonia, and both species are widely different from Puccinia 

 Viola. 



Puccinia effusa D. & H. 1895. Erythea 3: 81. 



I. yEcidia amphigenous, but chiefly hypophyllous, in large indefi- 

 nite clusters, often covering much of the leaf, noticeably extending 

 along the veins and petioles ; substratum somewhat thickened ; cups 

 broad and low, border white, irregularly and coarsely lacerate, some- 

 what recurved ; spores subglobose, somewhat angular from compres- 

 sion, minutely verrucose, 2027 ;j. in diameter. 



III. Teleutosori for the most part arising from the cups of the 

 aecidia, uncovered, elliptical, nearly black ; spores dark brown, ellip- 

 tical or oblong, slightly if at all constricted at the septum, inconspicu- 

 ously verrucose, 23-317^ broad by 37-50/4 long; wall moderately 

 thick ; apex rounded, usually not thickened ; base rounded or occa- 

 sionally slightly narrowed; pedicel hyaline, deciduous. 



