520 THE FUNGI WHICH CAUSE PLANT DISEASE 



S. cerasina Pk."^ 



Spots scattered or confluent, minute, subangular, brown or 

 reddish-brown; pycnidia pale, collapsing; conidia filiform, straight 

 or curved, 50-75 /* long. On cherry. 



S. pruni E."^ 



Spots dark brown, dry, subrotund, soon breaking out, 1-3 mm. ; 

 pycnidia brown, immersed, 60 /x; conidia linear, obtuse, 4 to 

 6-septate, 30-50 x 2 /*. On plum. 



S. limonum Pass, and S. sicula Penz, occur on citrus; 



S. glaucescens Trab. on the mandarin; 



S. loefgreni N. on oranges in Brazil; 



S. ampelina B. & C. on the grape. 



S. longispora Sh. (not Miy.) is found on the cranberry.^" 



S. graminum Desm."^"' 



Spots slightly elongate, pale, fuscous-margined, limited by the 

 leaf veins; pycnidia seriate or scattered, brownish; conidia very 

 slender, straight or curved, non-septate, but multiguttulate, 

 55-75 X 1-1.3 ft. 



This is a frequent saprophyte or weak parasite on wheat, oats 

 and numerous wild grasses. Under some conditions it becomes 

 an injurious parasite, especially upon winter wheat. 



S. tritici Desm. is closely Uke S. graminum.*'* 



It is associated with Leptosphaeria tritici on wheat. See 

 p. 258. 



S. glumarum Pass, is also found on wheat. 



S. nodorum Berk, occurs, particularly at the nodes, on the same 

 host. 



S. secalina Jancz. is on wheat and rye leaf sheaths; 



S. avense Frank, on Ifeaves of oat. 



S. longispora Miy. (not Shear) and S. curvula Miy. are on 

 rice. 



S. betsB West. 



Spots pale brown, white in the center, brownish-margined; 

 pycnidia epiphyllous, minute, black, prominent; conidia cylindric, 

 straight or curved, white in mass. 



It was noted by Humphrey "* causing a beet leaf spot. 



S. citrulli E. & E. 



Spots small, round, white, scattered; pycnidia mostly solitary, 



