I New York Agricultural Experiment Station. 545 



Harold Powell, who says ''': " This belt is due to any injury to the 

 epidermis of the fruit in its young stage, and is caused by the freez- 

 ing of the dew collected on these spaces." No other explanation so 

 completely harmonizes with all of the facts. The belting of apples 

 and pears on Long Island this season was probably caused by the 

 frost which occurred on the night of May 16. 



IX. A NEW LEAF-SPOT DISEASE OF APPLES. 



When I first came to Long Island the Station Horticulturist, 

 Prof. Beach, requested me to waich for a leaf-spot disease of apples 

 which he had observed at Westbury, Long Island, in the summer 

 of 1894. Early in May, 1895, I found it in abundance in Mr. 

 Hicks' orchard at Westbury and later at various other places on 

 Long Island. In Mr. Hicks' orchard it was so abundant that by 

 July 1 some trees were almost completely defoliated. This indi- 

 cates that it may become troublesome. 



The disease appears in the form of circular brown dead spots about 

 one-eighth inch in diameter. In the summer of 1894, Prof. Beach 

 failed to find on the spots anything which would give him a clue to 

 the identity of the fungus, but in 1895 I found it in fruit as early 

 as June 29. The month of July, being rainy, was favorable to its 

 development and it fruited abundantly. On each spot there appear 

 several black specks which, upon examination under the compound 

 microscope, prove to be spherical sacs (perithecia) filled with color- 

 less, one-celled elliptical spores. These are the characters of the 

 genus Phyllostitita. Saccardo has described Phyllosticta jnrina 

 which occurs on pear and apple foliage. This species, although 

 occurring frequently, has seldom been reported as doing damage. 

 Alwood^ has reported a Phyllosticta^ ^hich. he doubtfully refers 

 to P.pirina, Sacc, as doing serious damage to apples in Yirginia, 

 in the season of 1891. As, onv Phyllosticta did not agree with the 

 characters of P. pirina, I sent specimens of it to Prof. C. H. Peek, 

 who replied that it is a new species and that he has given it the 

 name Phyllosticta limitata. The spores are longer and larger than 

 those of P. jpirina. 



5 Garden and Forest, Vol. VIII. ]K)5, p. 417. 



1 Virginia Exp. Sta. Bull. No. 17. June, 1892, p. 62. 



35 



