EXOBASIDIUM 401 



large, 1-4 in number, spores sausage-shaped, hyaline, 11-13 

 X 5-6 //. Conidia hyaline, cylindrical, 7-8 X i /*. 



The life history of this fungus is not known. I have not 

 observed mycelium present in the stem bearing diseased 

 leaves, and its spasmodic appearance, at all events in this 

 country, is not favourable to the idea of resting mycelium. 

 I have observed it at infrequent intervals in Kew Gardens, 

 but never twice on the same bush, and am altogether at a 

 loss to account for its presence. Leaves bearing galls should 

 be removed and burned. 



Vaccinium leaf blister (Exobasidium vaccinii, Woron.) 

 forms large blisters on the living leaves, less frequently on 

 the petioles and young shoots of the bilberry, or whortle- 

 berry ( Vaccinium myrtillus}. Red or purple patches appear 

 on the upper surface of the leaves, the fruit of the fungus 

 appearing as a delicate white bloom, occupying corresponding 

 patches on the under surface of the leaf. 



The spores are narrowly fusiform, hyaline, 5-8 X 1-2 p. 



The fungus occurs on other species of Vaccinium, Andro- 

 meda, and Acrostaphylos in other European countries. Of no 

 importance as a parasite. 



Vine leaf blister (Exobasidium vitis, Prill. ^Aureobasi- 

 dium vitis, Viala and Boyer) has proved destructive in 

 French vineyards from time to time. Small spots first appear 

 on the grapes, which soon shrivel and die before attaining 

 full size. The flesh is found to be completely permeated with 

 mycelium. Livid patches first indicate the presence of the 

 fungus on the leaves. These patches, also those on the fruit, 

 are covered with a white bloom when the fungus is fruiting. 

 Leaves that are attacked assume a deep red colour and fall 

 early. The basidia are cylindric-clavate, and bear a varying 

 number of sterigmata, 2-9, mostly at the apex, but sometimes 

 a few are lateral. Spores variable in form and size, i2-i6x 

 4-6*5 p. These spores, according to Prillieux, germinate by 

 budding in a yeast-like manner, and may prove to be conidia, 

 preceding the true basidiospores. Only recorded from 

 France. 



-Prillieux, Malad. des Plantes Agric., i, p. 298 (1895). 

 Viala and Boyer, Comp. Rend., 1891, p. 1148. 



Var. tuberculatum (M 'Alpine). In this variety more or 



2 C 



