COLCHICUM SMUT 



227 



UREDINACEAE 



COLCHICUM SMUT 

 ( Uromyces colchict, Massee.) 



For three successive seasons the foliage of a bed of 

 Colchicum spedosum was completely destroyed by this 

 fungus, and during the third season plants of Colchicum 

 bavaricum and C. autumnak growing on either side of the 



Fig. 56. Uromyces colchici. i , portion of a diseased 

 Colchicum leaf; 2, a sorus or cluster of spores which 

 has ruptured the epidermis of the host-plant, x 10 ; 

 3, teleutospores, consisting of several cells united in a 

 cluster ; the central dark cells are fertile, the pale, peri- 

 pheral cells are sterile, x 300. 



diseased patch were also attacked, although escaping for 

 the first two seasons. The parasite attacks the leaves 

 only, commencing at the base of the leaf-sheath and 

 gradually extending towards the tip of the leaf. The lowest 

 and oldest leaf is first attacked. 



The sori or spore-clusters are very much larger than is 



