SPHAEROPSIS 413 



Lilac leaf spot (Phyllosticta syringae, Westend.). Very 

 frequent on living leaves of lilac, forming irregularly shaped, 

 rather large bleached spots surrounded by a brown border. 

 The minute, blackish, dot-like perithecia, containing numerous 

 minute hyaline, oblong conidia, averaging 8 X 3 ft. 



This parasite is widely distributed in Europe, in fact its 

 occurrence is that of its host-plant. 



Phyllosticta idaecola (Cooke) forms rather indistinct brown 

 spots with a whitish centre on living leaves of Sida napaea 

 and various species of Hibiscus grown in houses. Conidia 

 hyaline, elliptical, 4X2^. 



Phyllosticta helleborella (Sacc.) forms large ill-defined 

 blotches on the leaves of various kinds of hellebore. The 

 blotches are blackish at first but soon become pale with a 

 dark border, and studded with the minute, flattened perithecia. 

 Conidia oblong, colourless, 7 X 3 /*. 



Phyllosticta aceris (Sacc.) forms bleached spots on the 

 leaves, which become studded with the small dot-like fruiting 

 bodies. Conidia elliptical, 5 X 3 /*. 



Phyllosticta cytisi (Desm.) forms circular bleached spots, 

 that eventually turn brown, on laburnum leaves. Conidia 

 oblong, 6 X 3-4 /*. 



Phyllosticta priniulaecola (Desm.) forms rather large whitish 

 spots, with a tawny margin, on the leaves of Primula vera and 

 P. elatior, and may possibly pass to other species. Conidia 

 4-5 X 2-3 p. 



Phyllosticta cornicola (D. C.) produces rather large, blood- 

 red spots that become pale in the centre, on the leaves of 

 Cornus sanguinea and other species. Conidia elliptic-oblong, 



7-9 X 3-4 p. 



Phyllosticta apii (Halst.). This is figured and described in 

 the N. Jersey Agric. Exp. St. Rep., 1891, p. 253. It differs 

 from Cercospora apii^ in the spots on the leaf being dull brown, 

 never pale coloured. 



SPHAEROPSIS (LEV.) 



Perithecia distinct, slightly carbonaceous ; conidia con- 

 tinuous, escaping through a terminal pore. 



Apple leaf spot. Dr. W. M. Scott has shown that a serious 

 disease affecting apple leaves is caused by Sphaeropsis malorum 

 (Peck.) in the United States. It has also been recorded in 



