322 THE FUNGI WHICH CAUSE PLANT DISEASE 



E. australe Speg. 



Son foliar, forming spots, yellowish to eventually dark, usually 

 0.5-6 mm. in length; spores light to reddish-yellow, ovoid to 

 spherical or slightly angled, chiefly 10-16 n in length; conidia 

 Unear, somewhat curved, usually 30-55 x 1-2 ii. 



Common and destructive on many species of Physalis and on 

 Solanum, especially on some of the cultivated forms throughout 

 the Americas and in Africa. 



E. fuscum Schr."^ 



Sori in. leaves, about 2-6 mm. or by confluence much larger, 

 spores light yellow to chestnut-brown, provided (especiaUy when 

 young) with a conspicuously swollen gelatinous envelope, smooth, 

 chiefly 13-19 /i in length; the hypophyllous matted outgrowths 

 usually show few conidia which are fusiform, single-celled or sep- 

 tate, 10-22 X 3 M- 



It occurs on Papaver in Europe and Eastern North America. 



E. nymphaese (Cunn.) Set.^*' 



Sori in leaves, forming variable and irregular areas, usually 

 most prominent on the under side, yellowish or with age reddish- 

 brown, scattered or confluent; spores hyaline, ovoid to subspherical, 

 usually apiculate and with the remains of the hypha as a basal 

 appendix, smooth or under an immersion lens minutely verrucu- 

 lose, 10-14 /i in length; conidia not observed but spores said to 

 germinate in situ. 



On leaves of various water lilies in both the old and new world. 



Doassansia Cornu."^' ^^ (p. 315) 



Sori in various parts of the host, usually 

 in the leaves, rather permanently embedded 

 in the tissues; spore-balls conspicuous, per- 

 manent, consisting of a distinct cortical 

 layer and a central mass of fertile cells en- 

 FiG. 238. -Doassansia. ^'^^ly filling the interior, or with the inner- 

 Part section through most cells Supplanted by parenchymatous 



a spore ball showing i i i .1 1 1^ i- 



sterile and fertile cells, cells Or hyphal threads; spores hyalme or 



ter Dietei. yellowish, with smooth, usually thin, walls; 



germination often in situ, by means of a short promycelium which 



