﻿1903] RAVEN ELI AS OF THE UNITED STATES 127 



its sori. It differs from R. Pazschkeana Diet, in the unthickened apices of 

 its uredospores and in the longer papillae, and in being subcuticular while 

 R. Pazschkeana is sub-epidermal. 



PLEORAVENELIA, n. gen. 



Spermogonia formed between the cuticle and the epidermal 

 cells, hemispherical. Aecidia with a well developed pscudo- 

 peridium. Uredospores borne singly on short stalks ; germ pores 

 few or many; paraphyses usually present in the uredosori, Teleu- 

 tospores united into cushion-like heads formed of several or 

 many cells; inner teleutospores two-celled by transverse or 

 more or less oblique septa ; outer spores one-celled ; under side 

 of teleutospore heads with several or many hyaline cells or 

 cysts ; pedicel of the head of several hyphae, which are either 

 separate or united into a compound stipe.' 



KEY TO SPECIES. 



I. Teleutospore heads smooth 



Teleutospore heads rough, warty, etc. 



2 



3 



2. Uredospore germ pores many [(12-15). scattered; paraphyses many, 



clavate -..------/'. laevis 



Uredospore germ pores 6-13, equatorial ; paraphyses none - - 4 

 3- Uredospore germ pores many, scattered ; paraphyses many ; teleuto- 

 spore heads papillate - - - - - P. indigoferat 



Uredospore germ pores many, scattered ; teleutospore heads warty and 



appendaged at base 



P. brongniartiae 



Uredospore germ pores 4-6, equatorial ; teleutospore heads minutely 



verrucosa 



P. talpa 



4. Germ pores 6. Uredospores fulvous, 25 by 34 M - P- epiphylla 



Germ pores 8-12 ; uredospores brown, 20 by 25 m - - P- similts 



Pleoravenelia laevis (Diet, and Holw.) — Fig. 17- 



Rave7telza iaevisT>\^X, and Holw.,BoT. Gaz. 27:35. 1897 ; Saccardo, Syll. 

 Fung. 14:366. 1899. 



Sori subepidermal, on yellow spots on both sides of the 

 leaves. Uredosori cinnamon color, few. small, surrounded by 

 the ruptured epidermis; uredospores brown, oval to globose, 

 spinulose, 21-26 by 22/1; germ pores many (15 or more), scat- 



'The other Ravenelias with the inner spores two-celled, which are not included 

 in this paper, will also come under the new genus Pleoravenelia, and should be written 



Pleoravenelia Hieronymi (Speg), P. MacOwaniana (Pazschke), P. glabra (Kalchbr. 



and Cke.), and P, tephrosiae (Kalchbr.). 



