HEMILEIA 33i 



named Cattleya dowiana (Batem.), received at Kew on two 

 different occasions from Costa Rica, have had the leaves 

 suffused with broad patches of a powdery orange fungus, 

 which on examination proved to belong to the genus Hemileia. 

 Uredospores forming broadly effused, powdery, deep 

 orange - coloured patches, uredospores perfectly globose, 

 warted, two germ-pores, 24-32 /x. diam. 



Massee, Keiv Bulletin, No. 2, 1906. 



Hemileia oncidii (Griff and Maubl.) is parasitic on leaves of 

 Oncidium marshallianum, O. crisptim, and O. varicosum, and 

 has so far only occurred on cultivated plants in France. 



The fungus forms powdery orange spots on the under sur- 

 face of the leaves. Uredospores globose, echinulate, 16-18 /x. 

 Teleutospores springing from the centre of uredospore-sori, 

 subglobose or piriform, at first hyaline, aculeate, then pale 

 brown and almost smooth, 20-23X15-20 /x. Haustoria 

 elliptical or ovate, more or less lobed. 



Hemileia indica (Massee). Parasitic on the leaves of an 

 undetermined species of Macropanax, from India. 



Uredospores forming powdery orange patches, spherical, 

 warted, with a broad circular hilum or point of attachment 

 to the pedicel, about 25 /x diam. Teleutospores occupying 

 the central portion of uredospore head, broadly obovate to 

 subglobose, smooth, 18-20 /x diam. 



Massee, Kew Bulletin, No. 2, 1906. 



Pine cluster-cups (Coleosporium senecionis, Fries., = Pen- 

 dermium pini, Wallr.) has its aecidium stage developed on 

 pines. The aecidia are of two forms, one, cylindrical and 

 slender, formed on the leaves, a second, much larger and in- 

 flated, appearing in crevices of the bark of Pinus silvestris, 

 P. maritima, P. insignis, and P. strobus. The uredo and 

 teleutospore stages form effused orange patches on the under 

 surface of the leaves of groundsel, ragwort, and other species 

 of Senecio. 



Aecidiospores orange, warted, form variable, up to 40 X 

 17-28 /x. 



Uredospores in short chains, soon free, orange, warted, 

 20-40 X 14-26 /x. 



Teleutospores forming waxy, reddish-yellow crusts, cylin- 

 drical or cylindric-clavate, flattened, generally 4-celled, bright 

 rufous-orange, nox 17-35 I 1 - 



