90 QUINCE CULTURE. 



the quince cultivator, sometimes eats into corn and vari- 

 ous fruits. 



3. QUINCE LEAF BROWNNESS (Morthiera Mespili v. 

 Cydonice, C. and E.). This fungoid disease of the 

 leaves is indicated by reddish-brown spots, which show 

 on both sides of the leaf, with a small black speck in the 

 center of each spot, which speck, on being magnified, 

 appears to be four spores in one, each of the four being 

 elliptical, and ending in a thread as long as itself. The 



Fig. 61. LEAVES AFFECTED BY MORTHIERA MESPILI. 



rounded spots extend into coalescing brown patches, 

 sometimes covering a large part of the leaf. The en- 

 largement of the spots is due to the extension of the 

 mycelium of the spores, which, as the disease progresses, 

 kills the leaves, and they drop to the ground. The older 

 leaves generally show the disease first, and from them it 

 extends toward the ends of the branches, sometimes nearly 

 defoliating the tree. It occurs on trees of every age. 

 In studying this disease, Soraner put some spores on a 



