THE FUNGI WHICH CAUSE PLANT DISEASE 523 



depressed, brownish-black; cirri white; conidia elongate, cylindric, 

 curved, obtuse, 30-45 x 4 /t. 



It is the cause of a common and injurious leaf spot of the car- 

 nation. The pycnidia are visible as dark specks on the blanched 

 background of the spot. 



S. azalese Vogl. 



Spots reddish-yellow; pycnidia amphigenous, immersed, globose 

 to depressed, black; conidia oblong cylindric, filiform, straight or 

 curved, 1 to 3 or more septate, constricted slightly at the septa, 

 12-18 X 1.5-2.5 ii; conidiophores cylindric, short, 3-5 /x long. 



On Azalea. 



S. divfiricatse E. & E. 



Spots whitish, amphigenous, confluent, purple-bordered; pyc- 

 nidia numerous, epiphyllous, lenticular, 100-120 /*, dull black; 

 conidia 18-30 x 0.75-1 /*, nearly straight, non-septate, finely 

 guttulate. 



It frequently injures cultivated phlox.** 



S. narcissi Cass, is on Narcissus. 



S. exotica Speg. is on Veronicas in cultivation. 



S. fairmanii E. & E. 



Spots amphigenous, scattered, subangular, 3-4 mm. dark 

 brown, limited by the veins, with a narrow dark margin; pycnidia 

 epiphyllous, scattered, rather numerous, black, subprominent, 

 100-112 /i; conidia filiform, slightly curved, guttulate, 30-45 x 



1.5-2 M. 



It parasitizes hollyhock leaves." 



S. parasitica Fau. 



Spots amphigenous, white; pycnidia pimctiform, innate; conidia 

 cylindric, 30-40 x 3.5-4 pi. 



The conidia are broader than in the preceding species and the 

 gross appearance is quite different. It is found associated v/ith 

 rust sori on hollyhock.'^ 



S. helianthi E. & K. 



Spots brown, definite, 2.5-7.5 mm. with a yellowish elevated 

 margin; pycnidia epiphyllous, immersed, brown, collapsing, 105 m; 

 conidia linear-filiform, 3 to 5-septate, 30-70 x 2-3 m."^ 



On sunflower leaves. 



S. majalis Aderh. causes a leaf spot of lily-of-the-vaJley; 



