APPLE DISEASES. 199 



From nay study of this fungus in nature, in culture, and by 

 inoculations of fruit and wood of apple it shows the characters 

 of the genus, Phoma. Several species of Plioma are described 

 as occurring on apple branches. Phoma ponianDii Thijm. 

 occurs on the fruit of the apple in Europe but the spores of 

 that species do not agree with the spores of the fungus under 

 consideration. Phoma uiali Schulz. et Sacc. is described as 

 having spores 8 microns in length. Phoma ambigua (Nits.) 

 Sacc. agrees closely with Phoma mali having spores 8x3 

 microns. It has seemed best to the writer to refer this fungus 

 to Phoma mali Schulz. et Sacc. depending on the description 

 which has been given of the cultural characters and of the 

 effects on inoculated apples to enable other students of apple 

 diseases to determine whether or not they are working with the 

 same fungus. 



SUMMARY. 



Coryncum foliicohiin and Phoma inali cause disease of the 

 wood of young apple trees and of branches of old trees. These 

 fungi are more actively parasitic than Coniothyriiim piriiia. 

 As wound parasites, they attack young trees in such a way as 

 to do as much damage as Sphccropsis malorum but do not 

 spread so rapidly in the large branches of older trees. 



Coryncum causes only a slight decay while Phoma causes 

 a rather rapid and complete decay of ripe apples and can attack 

 the green fruit to some extent. 



Neither of these fungi has been found to cause disease of 

 uninjured leaves, but, in common with a number of other fungi, 

 they occur on dead spots in apple leaves. 



The distribution of these fungi can be largely controlled by 

 removing and bm-ning the dead wood on which they occur. 



LITERATURE CITED. 



1. Butler. E. J. The Mulberry Disease Caused by Cory- 

 neum mori Nom. with Notes on Other Mulberry Diseases. 

 Memoirs of the Department of Agriculture in India. Vol. II, 

 No. 8, pp. i-iT. 1909. 



2. Edgerton, Claude Wilbur. The Physiolog}' and Develop- 

 ment of some Anthracnoses. Bot. Gaz. 45 : p. 405. 1908. 



3. Hartley, Carl P. Some Apple Leaf-spot Fungi. Science 

 N. S. 28. 157-159. 1908. 



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