434 PLANT DISEASES 



up into bacteria-like segments, after producing terminal 

 spirillum-like ' spores ' by the coiling of their free extremi- 

 ties. Forming a firm, lichenoid pellicle on nutrient jelly, 

 and usually when growing in contact with the air produc- 

 ing a deep, black-brown discoloration of the substratum. 

 Producing the disease known as ' Scab ' on potato tubers, 

 and a similar affection of beetroots. 



The above is the author's amended diagnosis given in 

 Journ. My col, vii. p. 280 (1893). It is stated that the 

 fungus obtained accidentally from water by Sauvageau, and 

 described as Oospora metchnikowi {Arm. d. flnst. Pasteur, 

 tab. vi. p. 242) is probably identical with 0. scabies. 



Monilia, Pers. — Hyphae erect, vaguely branched, often 

 forming dense tufts, rarely effused, producing denticulate 

 conidiophores here and there ; conidia rather large, formed 

 in chains. 



Monilia fructigena, Pers., Syn., p. 693. — Tufts compact, 

 pulvinate, often confluent and forming concentric rings; 

 hyphae fasciculate, with short branchlets, which bear 

 simple or branched chains of ovoid, oblong, or lemon- 

 shaped, hyaline, or pinkish conidia, 25 x 10-12 [i. 



Dematiae.— Hyphae or conidia, or both, brown or 

 blackish. 



Fusicladium, Bon.— Hyphae short, straight, sparingly 

 septate, somewhat fasciculate, olivaceous; conidia ovoid 

 or subclavate, for a long time continuous, at length often 

 T-septate, acrogenous, solitary or in pairs. 



Fusicladium pirinum, Fckl, Sy7?ib. Myc, p. 357. — 

 Effused, olive, velvety; conidia ovate-fusoid, 28-30x7- 

 9 /x, continuous (always ?), guttulate, olive ; conidiophores 

 short, terete, apex denticulate. 



