SEPTORIA 423 



spraying instead with a solution of copper sulphate in water 

 one pound to fifty gallons of water. 



Halsted, Rep. N. Jersey Agric. Coll. Expt. Sta., 1894, 



P- 363- 



Salmon, Rep. Econ. Mycol., Wye Coll., 1908, p. 79. 



Chrysanthemum leaf scorch. Voglino describes a disease 

 of the cultivated varieties of chrysanthemum, in which the 

 leaves, more especially towards the margin, are of a thicker 

 consistency than normal, and of an intense black or blackish- 

 purple colour. This appears on the lowermost leaves first, 

 and gradually ascends until all the leaves are attacked. In 

 other instances the disease appears under the form of well- 

 defined circular, ochraceous brown spots, somewhat shining, 

 and bordered with black. Minute black points, the fruit of 

 the fungus, appear scattered over the surface of the leaf. The 

 injury is caused by Septoria chrysanthemi (Cav.) and its 

 pycnidial form, named Phoma chrysanthemi (Voglino). 



Septoria form. Perithecia completely immersed, globose ; 

 conidia hyaline, almost filiform, 6-10-septate at maturity, 

 60-75x2-2-5 /j.. 



Phoma form. Perithecia subglobose, black, almost super- 

 ficial, minute; conidia hyaline, elliptic-oblong, 7-10X3-4 p.. 

 2-guttulate. 



Voglino, P., Malpighia, 15, p. 329 (1901). 



Pear leaf spot, caused by Septoria piricola (Desm.), is a 

 common disease throughout Europe and the United States, 

 and in all probability occurs wherever the pear is cultivated. 

 It appears under the form of small, somewhat angular, greyish 

 spots on the leaves, on which the minute black spore-cases 

 can be seen by the aid of a magnifying-glass. When the spots 

 are numerous the leaves turn yellow, and fall quite early in 

 the season. The fruit is not attacked. 



The minute perithecia are embedded in the substance of 

 the leaf, a small open mouth piercing the epidermis, through 

 which the spores escape in the form of a long, dark coloured, 

 viscid tendril. Spores hyaline, long, almost filiform, one end 

 slightly thickened, often slightly curved, usually 2-septate, 

 60X3*5 l x - Tubeuf says this fungus is probably a stage of 

 Sphaerella lucillae (Sacc.) ; however, no direct experiment has 

 proved this statement to be correct. 



