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cultivated apple has been attacked for many years in the eastern 

 United States, it is only in recent years that this fungus has ap- 

 peared on the cultivated apple in the central states. In discussing 

 an outbreak of apple rust in Iowa during the summer of 1905 

 Pammel made the following statement, "In my observations 

 and experiments, extending ov< 

 this state, I have never [before] s 

 That it may become a very serious enemy to apple culture in the 

 state cannot be doubted." His prediction has been fulfilled. 

 G. globosum, most commonly found on the hawthorns (Crataegus), 

 also attacks the leaves of the cultivated apple in the New England 

 states. So far as the writer knows, it has been reported on that 

 host only from Maine, Vermont, Massachusetts, Connecticut 

 and New York. In Europe G. juniperinum (G. tremelloides) is 

 the only species which attacks the apple. In parts of Europe, 

 especially northward, it is often reported as abundant and severe. 

 Although this species also occurs in America it has not yet been 

 found here on the apple. 



The pear (Pyrus communis) is occasionally attacked in the 

 eastern United States by G. globosum which is usualy confined to 

 the leaves. Stewart (1910), who has had under observation a 

 Kieffer pear orchard on Long Island, N. Y., reports the presence 

 of this rust each year since the trees were planted in 1903 and ob- 

 serves that prior to 1910 only the leaves were affected, while during 

 the season of 1910 both leaves and fruit were severely attacked. 

 G. Sabinae, of Europe, has the pear as its chief aecial host and 

 its injury to pear culture there has long been recognized. 



In America the quince (Cydonia vulgaris) is frequently attacked 

 by G. germinale (G. clavipes) and more rarely by G. Nidus-avis, 

 the former often producing injury of practical importance. Both 

 quinces and pears have occasionally been attacked in Colorado 

 by a roestelia which the writer has referred to G. Nelsoni. In 

 Europe G. clavariaejorme and G. Mespili (G. confusum) attack the 

 quince. 



From the point of view of the genus Juniperus the species of 

 Gymnosporangium just mentioned in the foregoing discussion of 

 orchard crops are, perhaps, the more important, since they are 

 the ones which are naturally most likely to occur on those red 

 vind breaks or for decorative 

 nity of orchard trees- 



