248 B7dtish UrcdinecF and Ustilaginece. 



Teleutospores — Sori vernal on last year's living leaves, whitish or 

 pinkish, often covering the whole leaf-surface. Spores spherical 

 or shortly prismatic, in section polygonal, membrane thick, 

 smooth, colourless, contents very pale reddish, simple, inter- 

 cellular, 13-15/X in diameter. Promycelial spores globose, 

 8-1 o/A, colourless. 



Syfionyms. 



Schrot, loc. cit., p. 366. Winter, loc. cit., p. 242. 



Uredo piistulata, var. cerastii. Pers., " Syn.," p. 219. 



Uredo caryophyllacearum. Johnst., " Flor. Berw.," vol. ii. p. 

 199. Berk., " Eng. Flor.," vol. v. p. 381. Cooke, " Hdbk.," p. 

 526 ; " Micro. Fungi," 4th edit., p. 216. 



Exsiccati. 

 Cooke, i. 6 ; ii. 75 ; " L. R," 30. Vize, " Fungi Brit.," 145. 



On Cerastium arvense, Stellaria graminea. 



Biology. — We are indebted to Schroter for the life-history of this 

 fungus. The uredospores first make their appearance in June, and 

 are found throughout the summer until October. The teleutospores 

 are found in the following year in May and June, in colourless or pale 

 flesh-coloured sori on those living leaves which have survived the 

 winter. 



COLEOSPORIUM. Lev. 



Teleutospores composed of several superimposed cells enclosed 

 in a thick transparent membrane, confluent in flat waxy masses. 

 Each cell germinates by a single unseptate promycelial tube, 

 which produces at its end a single promycelial spore. Uredo- 

 spores formed in basipetal chains. 



I. EUCOLEOSPORIUM. Winter. 



Heteroecious, having spermogonia, secidiospores, uredospores, and teleuto- 

 spores. 



Coleosporiuni senecionis. (Pers.) 



j^cidiospores — Of two kinds, (i) On the fir needles, scattered or 

 in small groups. Pseudoperidia cylindrical or laterally com- 

 pressed, mouth torn irregularly, 2-2-5 i^""^- high- (2) On the 



