2 54 British UredinecE and Ustilaginece. 



CRONARTIUM. Fries. 



Teleutospores unicellular, compacted into a cylindrical body, 

 germinating at maturity on the living host-plant. Promycelial 

 spores almost spherical, pale. Uredospores enclosed in a pseudo- 

 peridium, which surrounds the base of the cylinder of teleutospores. 



Cronartium flaccidum. Alb. and Schw. 



Uredospores — Sori small. Pseudoperidia broadly conical, dark 

 yellow, persistent. Spores elliptical or ovate, echinulate, 20-30 

 X 13-20/i.. 



I'eleutospores — Sori cylindrical, often curved, about 2 mm. high. 

 Spores oblong or cylindrical, brown, 10-12/A across. 



Synonyms. 



Sphccriaflaccida. Alb. and Schw., "Consp.," p. 31. 

 Cronariiuni pa'onm, Cast. Cooke, "Micro. Fungi," 4th edit, 

 p. 215. 



Cronartium flaccidum (Alb. and Schw.). Winter, loc. cit., p. 236. 



On Fivonia officinalis. In gardens. North Wootton ; C B. P. 

 South of England ; Miss Jelly. 



APPENDIX. 



Imperfect Forms, of which the Full Life-History is 



UNKNOWN. 



UREDO. 



Spores produced singly on the terminal ends of mycelial 

 hyphae (basidia). Germination by a germ-tube which does not 

 produce promycelial spores, but enters the host-plant through its 

 stomata. 



