PLATE 78 



A. — A young seedling (3 weeks old) of Saccharum spontaneum infected with 

 Sclerospora spontanea. On this seedling, which was artificially inoculated on the 

 second night after it emerged, conidium production began on the sixth night following 

 and recurred in increasing abundance on successive nights. In contrast to healthy 

 seedlings this plant betrays the effect of the Sclerospora in its pallor and in the presence 

 of a whitish " down" of conidiophores. These have collapsed on drying but can still 

 be seen on that part of the fourth leaf indicated by the pointer. X f£. 



B. — Conidiophores on the leaf of Saccharum spontaneum. A portion of the upper 

 leaf surface of a downy-mildewed plant (PI. 77, B) showing remains of the whitish 

 "down" of innumerable conidiophores produced during the night. Although photo- 

 graphed as early as light would permit, the leaf surface has dried somewhat and the 

 fragile conidiophores have shrunk and matted together. X iK- 



C. — Young shoots of Saccharum spontaneum arising after the primary stalk had been 

 cut, and like it severely infected with Sclerospora spontanea. The main plant, one of 

 the four downy-mildewed ones transplanted from Cebu, was cut off close to the ground. 

 All the subsequent shoots arising from the remaining base were, from the first leaf, 

 badly infected with Sclerospora and produced abundant conidiophores. 



