172 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



DISEASED PELARGONIUMS FROM THE TRANSVAAL. 



By Geo. Massee, F.L.S., V.M.H. 



In February last the Secretary of the Royal Horticultural Society 

 received from Mr. John Dowie, Fordsburg, Transvaal, specimens of 

 diseased leaves of English and French varieties of Zonal Pelargoniums. 

 The only remark in the letter accompanying the specimens was to the 



Fig. 59.— Diseased Pelargonium. 



1. Leaf attacked by the uredo stage of Puccinia granulans. Nat. size. — 

 2. Groups of uredospores bursting through the epidermis of the leaf. 

 x 40.— 3. Groups of teleutospores bursting through the epidermis of the 

 leaf. x 40. — 4. Uredospores. x 400.— 5. Teleutospores. x 400. 



effect that plants grown under glass were more susceptible to the disease 

 than those grown in the open air. 



Microscopic examination showed that the disease was caused by a 

 minute parasitic fungus called Fuccinia granulans, Kalch. and Cocke, a 

 pest allied to the wheat mildew — Puccinia graminis, Pers., and, like the 

 latter, producing different kinds of spores or reproductive bodies during 



