DISEASES OF THE QUINCE. 91 



healthy pear leaf, which there germinated, and in two 

 weeks produced the brown spots with the black specks in 

 the center. In the winter he found on the fallen leaves 



Fig. 62. MORTHIERA MESPILI, MAGNIFIED Fig. 63. MYCELIUM OP 

 400 DIAMETERS. THE FUNGI MAGNIFIED. 



what he thought to be the same fungus, producing an- 

 other set of spores (ascospores), which became ripe in 

 April and May. Such fungi are able to grow slowly 

 through the winter, ready to spread the disease on the 

 new leaves in the spring. He also found the fun- 

 gus capable of wintering on the bud-scales, without 

 entering on a second stage of development. Young 

 and weakly trees are more susceptible to its attacks than 

 stronger growing trees. The pear and thorn are also 

 subject to its attacks. The only sure remedy is to gather 

 and destroy the leaves. 



4. YELLOW LEAF SPOTS (Hendersonia Cydonice, C. 

 and E.). This is another fungus on 

 quince leaves, resembling the Morthiera 

 mespili, except that the spots on the 

 leaves are yellow and produce a thick- 

 ening of the leaf, with a development 

 on the under side of the spots like the 

 bursting of the cluster cups of the Rces- 

 tilia aurantiaca, only smaller. The HENDERSONIA CT- 

 spores are elliptical, marked with three DONIA, MAGNIFIED 

 bars across, dividing them into four 400 DIAMETERS. 



