578 



FUNGI IMPERFECTi: THE IMPERFECT FUNGI 



KV'rir^ 



Fig. 191. Sphaeropsidales, Family Sphaeropsidaceae. (A-C) Phyllostida tabifica 

 Prill. (A) Pycnidium viewed from above, showing cirrhus of spores. (B) Vertical sec- 

 tion through pj^cnidium. (C) Spores. (D, E) Dendrophoma convallariae Cav. (D) 

 Pycnidium from above. (E) Conidiophores. (F) Ascochyta dianthi (A. & S.) Berk.; 

 section through pycnidium. (A-C, after Prillieux: Bull. soc. mycol. France, 7(1):15-19. 

 D-E, after Briosi and Cavara: Fascicle IV, No. 89. F, ibid., Fascicle XIV, No. 342.) 



on the roots and inflorescence has been called Phoma betae Fr. Various 

 species of these genera have been shown to have as their perfect stage 

 species of Guignardia, Mycosphaerella, etc., in the Sphaeriales or Pseudo- 

 sphaeriales. The specific distinctions have to a considerable extent been 

 based on the host species attacked. Until very extensive inoculation ex- 

 periments can be carried out, this basis for segregation of species will 

 probably continue to be used. Cyiospora and Ceuthospora (Hyalosporae) 

 produce their pycnidial cavities in subepidermal or subcortical stromata. 

 The spores emerge from the separate or united ostioles in an amber- 

 colored cirrhus. Many of the species are the imperfect stages of Valsa and 

 related genera in the Sphaeriales. (Fig. 192A.) Sphaeropsis (Phaeosporae) 

 corresponds to Macrophoma except that the conidia are dark-colored. S. 



