THE RUSTS OF NOVA SCOTIA. FRASER. 413 



Arthur (Mycol. 2:227. 1910) states that, though in the 

 uredinial stage this rust shows racial strains that inhibit the 

 ready transfer from one species of host to another, yet in the 

 aecial stage racial strains play no part, and the barberry acts 

 as a bridging host between each and every other gramineous 

 host. 







Puccinia phlei=pratensis Erikss. and Henn. 

 & I. Pycnia and aecia unknown. 



II. Uredinia amphigenous, mostly epiphyllous, on the 

 stem linear and breaking through the epidermis by a lateral 

 fissure, on the leaves scattered, small and oblong, pulverulent, 

 yellowish-brown. Urediniospores ellipsoid, oblong-ellipsoid or 

 obovate, 16-21 by 24-32ju; wall dull yellow, echinulate. 



III. Telia similar to the uredinia but blackish-brown, 

 mostly on the stem. Teliospores mostly elongate, 16-20 by 

 35-48/x, rounded or somewhat acute above, narrowed toward the 

 base, slightly constricted at the septum; wall chestnut-brown, 

 thickened at the apex, usually 5-8/*, smooth; pedicel persistent, 

 strongly tinted, thickened, usually longer than the spore. 



On PJileum pratense L., Pictou. 



In 1894 Ericksson and Henning separated the timothy rust 

 as a distinct species, on the ground that it does not form its 

 aecial stage on the barberry. Previously it was considered as 

 identical with Puccinia graminis, from which it cannot be 

 separated on morphological grounds. Kern (Torreya 9:3, 

 1909) points out that in Eriksson and Henning's original 

 report, out of nine trials to infect the barberry with teliospores 

 of the timothy rust one was successful and eight were failures. 

 He thinks that more weight ought to be given to the one 

 positive result than to all the failures, and concludes that the 

 timothy rust may be considered a race or physiological species 



PROC. & TRVNS N. S. INST. Sci. VOL. XII. TRANS 28 



