1 68 Bintish Urcdinece and Ustilazineo'. 



c3 



^cidiospores on Anchusa aj'veusis, Echiuni vulgare, September 

 and October. 



Teleutospores on Bromus mollis, Triticum znilgare, repens, 

 sativum, Secale cereale, Hordeum vulgare, Holcus lanatus, mollis, 

 Avena saliva, elatior, from November to August. 



Biology. — Mesospores are not uncommonly mixed with the normal 

 teleutospores, especially when the fungus occurs on any of the genus 

 Hordeum = van simplex, Kornicke, and P. anomala, Rost. The 

 mesospores are about 45^1 long. The teleutospores germinate in the 

 autumn of the year in which they are produced ; hence the a;cidium is 

 to be found on Anchusa arvetisis in September and October. The 

 knowledge of this fact only came recently under my notice. In 1885, 

 I laid a bundle of wheat straw affected with P. rtibigo-vera in my 

 garden, near some plants of Anchusa, in August, with the intention of 

 doing some cultures in the following spring. In September, I found 

 to my surprise the secidium appearing on the Anchusa. This was the 

 more remarkable, because I had never previously found the aecidium, 

 and the plants of Anchusa had been growing all the year in the garden 

 perfectly healthy. The uredospores are exceedingly abundant in 

 spring, on wheat plants, in many parts of England, but the Puccinia, 

 unlike P. graminis, has very little prejudicial effect upon the crop. 

 Nielsen also finds P. rubigo-vera germinates in autumn. It is very 

 possible that more than one species is included under P. rubigo-vera. 



Puccinia poarum. Nielsen. 



y^cidiospores — Spots yellow above, often surrounded by a violet 

 margin, slightly thickened, concave. Pseudoperidia flat, with 

 whitish torn edges. Spores subglobose, finely echinulate, 

 orange-yellow, 18-24 x i5-i8yu. in diameter. 



JJredospoi-es — Sori small, round or elliptical, orange. Spores 

 spherical or elliptical, echinulate, yellow, 20-30/x in diameter. 

 Without paraphyses. 



Teleutospores — Sori small, black, persistent, usually circinating, 

 covered by the epidermis. Spores elliptical or clavate, very 

 variable, apex flattened or canically thickened, dark brown, 

 35-45 X 18-25/X. Pedicels very short, persistent, brownish. 



Synonyms. 



Puccinia poarum. Nielsen, " Bot. Tids.," vol. ii. p. 26. 

 Winter in Rabh., " Krypt. Flor.," vol. i. p. 220. 



