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PP- 5°~5 2 (Bull. XIX) of the current year. Whether the 

 fungus attacks the apple flowers and destroys them, or whether 

 it reserves its attack till the young fruit is set, is an im- 

 portant point raised in this Bulletin ; and it will be noted that 

 our negative conclusions as to the first proposition, made quite 

 independently, agree substantially with the authorities quoted on 

 p. 48 of that publication. Subsequent inquiries developed the 

 fact that in certain sections, the cherry blossoms withered and 

 fell in clusters, much as the apple blossoms did The Fusicla- 

 dium does not attack the cherry, indeed no destructive fungus is 

 known on young cherries likely to produce the effect mentioned. 

 The failure of the apple crop, therefore, during the last season, 

 was probably due primarity to a physiological disturbance (too 

 low temperature at the time of the blossoming, it is thought) ; 

 the young fruits which survived this first shock were then at- 

 tacked by the apple-scab and the curculio, the conditions 

 favoring the activity of both. The trees were also weakened by 

 the attack on the foliage of the apple-scab, and the wholesale 

 destruction of the crop under these circumstances is not surprising. 

 Careful observations will be made in the future to ascertain if the 

 fungus does or does not attack the flowers, as work will be con- 

 tinued on this disease during the winter and spring. 



Pear leaves, greatly discolored by a blackish blister, were sent 

 in at various times during the summer. In answers, and in Bul- 

 letin XIX, is indicated my belief that it was not due to a fungus 

 but to the work of a gall-mite. I am glad to call the attention of 

 correspondents to the timely paper by Professor Comstock on 

 this gall-mite, (Phytoptus pyri), on p. 103 of Bulletin XXIII, 

 a paper called forth by the above mentioned interest on this 

 disease. 



There seem to be two aspects to the destructive " Clematis 

 disease." Prof. Comstock, in his exhaustive paper on the Nem- 

 atodes, has made clear the relations of these parasites to the 

 Clematis roots ; but he has called my attention to the evi- 

 dence that the presence or absence of the nematodes has in many 

 cases no relation to the disease. Material has been secured and 

 work just begun, with a hope of finding something further in re- 

 gard to the origin of the disease. 



The Hollyhock Rust has been at intervals under examination 

 and many facts and observations collected concerning it, with the 

 expectation of continuing the work into next season. 



