

AMERICAN UREDINE^E. 189 



1896. Puccinia smilacearum-digraphidis Kleb. Zeits. f. 

 Pflkr. 6:261. 



0. Spermogonia epiphyllous in small clusters, puncti- 

 form, rather prominent, orange-colored; spermatia ellipti- 

 cal, about 3 by 5 ft. 



1. ^Bcidia small,, hypophyllous on yellow spots, in 

 circular clusters, often irregularly confluent; margin nearly 

 entire, slightly recurved; spores subglobose, 20-26 ^ in 

 diameter, peridial cells subglobose, somewhat angular, 

 28-32 by 24-28/*. 



II and III. Sori numerous, very small, elliptical to 

 shortly linear, on both sides of the leaf; uredospores 

 yellowish-brown, echinulate, obovate to globose, 24-32 by 

 16-20 /*, pores scattered: teleutosori black, covered by the 

 epidermis: teleutospores oblong or wedge-shaped, more 

 rarely shorter and elliptical, apex sightly thickened, 

 generally darker, rounded, truncate, oblique, or rarely 

 pointed, smooth, brown, mostly 44-52 by 16-24 /*; pedicel 

 short or wanting; paraphyses none. 



Exsic : 



Ellis, N. A. F., 229 ! , 1421 » , 1475 l > ' . 



Sydow, Uredineen, 95 , , 96 *. 



Rabenhorst-Winter, Fungi Europaei, 3024, 3026a, b & c. 



Thuemen, Myc. Univ., 27 '. 



Kunze, Fungi seel, exsicc., 554 >. 



The Puccinias on Phalaris arundinacea have been 

 divided into several so-called physiological or biological 

 species. Dr. Dietel defines the former as species morpho- 

 logically similar, but whose teleutospores are only able to 

 produce the aecidium from which they themselves were 

 derived. Klebahn describes biological species as fungi 

 that are indistinguishable morphologically, but are clearly 

 separated from each other by the choice of host 

 plant upon which they develop. The question has been 

 raised whether they are entitled to this designation, or 

 whether they are to be regarded as "biological races. " 



