1886.] NATURAL SCIENCES OP PHILADELPHIA. 323 



time no one has intimated any knowledge of it. In a recent 

 letter Dr. Masters, editor of the Gardeners' Chronicle of England, 

 says that no such disease has been recognized in the British Isles. 

 The testimony of one of our own horticulturists. Prof. Budd,' of 

 Iowa, who is familiar with the disease in this countrj'', and has 

 inspected the orchards of the old world far into Russia, is especi- 

 ally valuable ; he says " no trace of blight of pear- or apple-trees 

 can be seen in Europe." From these statements, and the infer- 

 ences to be drawn from other sources, it appears highly probable 

 that the disease does not extend to Europe. An account of the 

 principal diseases of fruit-trees of New Zealand, by Prof. T. Kirk,^ 

 has been published, which describes a disease of the pear known 

 in that country aspire blight, due to a fungus, and another of the 

 apple, the American blight, due to an insect. No true pear blight, 

 as recognized in the United States, is mentioned, and in a recent 

 communication the author has definitely stated that it is not 

 known in the colony. Whether it occurs in other parts of the 

 world is not yet ascertained, if some slight testimony regarding 

 its absence in Japan be excepted. 



It is only within a year or so that Eui'opean writers have become 

 aware of its existence, and this only through American authors. 

 It is remarkable that a disease of such virulence and so easily 

 transported should not have found its wa}' across the ocean, when 

 one remembers the number of destructive plant maladies that 

 America has ah'eady involuntarily foisted upon European culti- 

 vators. It will not be profitable to speculate much at this time 

 upon the reasons for this, but we may suppose that the small 

 exportation of American fruit-trees, or of scions,^ has been a 

 factor in keeping it in check. The influence of climate, and some 

 less evident factors, need not be discussed in this connection. 



Amount of Loss. It has already been intimated that pear 

 blight is a frequent and destructive affection ; it will tend to give 

 a fairer appreciation of the subject if it be stated how frequent 

 and how destructive it is. Coxe,* as early as 181T, in the oldest 

 pomological work by an American author, says it " frequently 



^ Trans. Minn. Hort. Soc. for 1883, p. 281. 



* Fruit Blights and Diseases of Fruit-trees in New Zealand, 1885. 



' For an account of the destruction of stored scions by blight, see Rep. 

 Hort. Soc. of Mich, for 1881, p. 137. * L. c, p. 174. 



