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 8X3/*. 



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 Si da napaea 

 and various species of Hibiscus grown in houses. Conidia 

 hyaline, elliptical, 4X2 fi. 



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, 5X3 p. 



Phyllosticta cytisi (Desm.) forms circular bleached spots, 

 that eventually turn brown, on laburnum leaves. Conidia 

 oblong, 6 x 3-4 /x. 



Phyllosticta primulaecola (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 fi. 



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 11. 



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 



