218 



Mycologia 



1049, 1245, 1346, 1547—222, 637, 844, 944, 1025, 1047, 1 152, 

 1244, 1345, 1446; Barth. Fungi Columb. 2350, 2447, 2555, 2556, 

 3060, 3758, 4148, 4461, 4664, 4962—3757, 3843, 39' 2 8, 3940, 4147, 

 4264 ; Brenckle, Fungi Dakot. 243, 365 — 301 ; Clements, Crypt. 

 Colorad. Form. 596; Ellis & Ev. Fungi Columb. 1904, 2101 ; 

 Kellerm. Ohio. Fungi 14Q — 81, 121 ; Kellerm. & Sw. Kansas Fungi 

 27. 



A Carex rust associated with aecia on Ribes is one of the most 

 widespread species both in Europe and America. The study of 

 these forms in America has been attended with some interesting 

 developments. In 1901 when Arthur made the first culture in 

 this country on Ribes the resulting aecia were characterized by a 

 decidedly whitish peridium apparently quite unlike the deep 

 orange aecia which are so abundant in North America, and the 

 species was named Puccinia albiperidia. During the next few years 

 every effort was made to determine the possible significance of the 

 pale forms obtained by cultures. After six or seven years of 

 culture work it was concluded that the greenhouse conditions 

 such as shade and moist air coupled with a slower development of 

 the fungus tended to produce the differences known to exist be- 

 tween the culture and field specimens. Plants infected indoors 

 and then transferred to the garden gave practically the same ap- 

 pearance as natural infections. The question as to the identity 

 between American and European material remained unsettled and 

 the American rust was still called Puccinia albiperidia. In 

 Europe several races were recognized and several names such as 

 Puc. Ribis-nigri-acutae and Puc. Rib esii-Pseudocy peri proposed 

 by Klebahn came into use. Just about the time that the con- 

 clusion was being reached that all Carex rusts both in Europe 

 and America, having their aecial stages on Ribes, were races of 

 one large species for which the name Puc. Grossulariae was the 

 oldest and most appropriate name, another disturbing factor came 

 to light. 



While making a special study of the Carex rusts possessing 

 1 -celled teliospores (Uromyces or Nigrcdo) some specimens were 

 found having one pore, near the hilum, in the urediniospores (see 

 Rhodora 12 : 124-127, 1910). At first this Uromyces was known 

 only on Carex tenuis but later it was found on C. gracillima. 



