Classification. 113 



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Peronospora injgmcBaj Cke. Hclbk. n. 1776; Cke. 

 Micr. Fung. t. 15, f. 2G7. 



On leaves of various ranunculaceous plants, as 

 Anemone nemorosa, and on otlier species of Anemone, 

 Aconitum, Hepatica, Isopyrum, &c. Local. 



Forming very minute wliitisli tufts^ that become 

 greyish-brown. The gonidiophores are often un- 

 branched, and towards the apex furnished with 2 — 5 

 spicules bearing the gonidia. 



Plasmopava nivea, Schroet. — (figs. 66-70). 



Mycelium stout, often torulose or variously con- 

 torted, haustoria numerous, piriform ; gonidiophores 

 fasciculate, rather short, 250-300x8-10 fi, tapering 

 upwards, simple, or once or twice bi-, trifurcate, with 

 1-4 usually very short spreading branches, rarely 

 elongated, these in turn are once or twice bi-, trifurcate 

 at the apex, ultimate branchlets conico-subulate, 

 spreading, straight, rarely slightly flexuous and bear- 

 ing the broadly elliptical gonidia, which have a very 

 thin, hyaline membrane, apical papilla very indistinct, 

 protoplasm granular, 21-25x15-18 /a; oogoniair- 

 regularly spherical, hyaline or pale yellow ; oospore 

 globose, large, yellowish-brown, smooth or minutely 

 rugulose. 



Tlasmopara nivea, Schroet. Krypt. Fl. Schles. 

 p. 237 ; Sacc. Syll. vii. 808. 



Peronospora nivea, De Bary, Ann. Sci. Nat. ser, 

 iv. vol. XX. p. 105; Cke. Hdbk. n. 1775; Unger, 

 Bot. Ztg. 1847, p. 314 (in part). 



On living leaves of various umbelliferous plants, as 

 Mgopodiumpoclagraria, A nthriscus sylvestris, Angelica 

 sylveatris, PimpineUa magna, P. saxifraga, Sium 



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