404 



THE FUNGI WHICH CAUSE PLANT DISEASE 



clavate, swollen; sterigmata 4; spores oblong, slightly flattened on 

 the side adjacent to the companion spores, tapering slightly at 

 each end, 4.7-5.8 x 10.5-11.6 /x. A migratory mycelium is 

 present, covering twigs and leaves with a brown felty growth; 

 rhizomorphs white, later buff, about 5.8 ii, septate. Sclerotia 

 are also found. 



The long cottony rhizomorphic strands extend along the twigs, 

 up the petioles and in places aggregate to form brown sclerotia, 



Fig. 291.— Hypochnus, 

 semi-diagrammatic sec- 

 tion showing develop- 

 ment of hymenium and 

 basidia, with nuclear 

 conditions. After Har- 

 per. 



Fig. 292. — Mycelium 

 of Hypochnus show- 

 ing clamp connec- 

 tions. After Har- 

 per. 



which are especially abundant near the terminal buds. On the 

 leaves Stevens and Hall *^ ** describe a loose network from which 

 the basidia arise. Fig. 295. The species is found on apple, pear, 

 lilac, quince, Vibemum and probably other hosts, and is widely 

 distributed. 



H. cucumeris Frank. 



Fungus gray or brown; basidia elongate, bearing 4 sterigmata; 

 spores ovoid hyaline. Reported on cucumbers *"• ^* in 1883. 



H. solani P. & D. is said to be a parasite of potatoes.''' It is 

 probably identical with Corticium vagum solani. See p. 407. 



