FUNGOID PESTS OF CULTIVATED PLANTS. 77 



contact (10-15 ^u). The sterile spores of the circumference are pale, some- 

 times in two strata, and also compressed where they come into contact 

 (7-11 [x diam.). When mature the spores are sprinkled about over the 

 foliage in an unsightly manner. The disease is liable to attack species of 

 Scilla and Muscari if found in proximity. 



Spraying the plants early with Condy's fluid has proved to be 

 preventive. 



Known in Italy, Belgium, and Germany. 



Sacc. Syll. vii. 1895; Mass. PL Dis. 227, 404; Cooke M. F. 232; 

 Mass. B.F. 186 figs. 86, 87 ; Cooke Hdbk. No. 1539 ; Ploivr. Brit. Ured. 

 286 ; Card. Chron. Sept. 30, 1876, fig. 



Colchicum leaf-spots are also known in Italy and France. 



Colchicum Rust. 

 Uromyces Colchici (Mass.), PI. V. fig. 93. 



At present this is solely a British product, and has for three successive 

 seasons completely destroyed a bed of Colchicum speciosum, and has 

 latterly attacked plants of C. bavaricum and C. autumnalc growing in 

 the neighbourhood. 



The parasite attacks the leaves, commencing at the base of the leaf- 

 sheath, and gradually extending towards the tip of the leaf. The oldest 

 leaves are the first to be attacked. 



The pustules are large for the genus, and often elongated on the 

 sheaths, whilst upon the leaves they are liable to be collected in circular 

 groups. They remain for a long time covered by the cuticle, which is 

 finally ruptured to set the teleutospores free. 



Teleutospores broadly elliptical or subglobose, with the apex slightly 

 prominent, epispore, or spore coat smooth, dark brown, and as much as 

 2/x thick (28-38 x 21-28 /*) seated upon a hyaline persistent pedicel. 



Cluster-cups or Uredo unknown. 



No remedy has been proved to be successful. 



Grevillea, xxi. 6 ; Mass. PL Dis. 226, 406. 



■ The species of Veratrum are very subject to parasitic diseases in North 

 America. 



Dracontium Cluster-cups. 

 JEcidium Dracontii (Schwz.). 



These cluster-cups are found in gardens on the leaves of Arum tri- 

 phyllum, and were first made known in the United States. 



The spots on the leaves are pallid and broadly extended, sometimes 

 occupying nearly the whole leaf. The cups are rather large and distinct, 

 being scattered without order over the spots, and not clustered as in 

 JEcidium Ari. The secidiospores are subglobose and of orange-brown 

 colour, somewhat angular by compression and minutely rough (15-16 fj. 

 diam.). 



It is scarcely probable that remedies will have to be sought after for 



