Curl of the Peach- Leaf. 223 



CURL OF THE PEACH-LEAF. 



Every spring, those who cultivate the peach must have noticed that the 

 first leaves become more or less distorted and swollen ; turn a variety of 

 colors, — yellowish, whitish, crimson, and purple ; and soon afterwards drop. 



On searching such leaves, oftentimes multitudes of green lice {Aphis sp.) 

 would be found nestling in the depressions and sinuosities produced by 

 the unnatural growth. The evil is often attributed to the presence and 

 action of these little insects ; and also to numerous ants, which are very 

 busy among the supposed insect depredators. Similar results may be 

 traced to a similar presence of ant and aphis on the growing shoots of the 

 yEnothera bien?tis, and of many succulent and quick-growing perennials 

 raised in the garden. The similarity of the two appearances does not, 

 however, indicate the same fact. 



The morbid condition of the foliage of the peach, with which we have 

 at present to do, has given rise to various conjectures and theories as to 

 its cause, attributing its appearance and subsequent development to cold 

 weather, unfavorable soil, or to sudden atmospheric changes. But having 

 noticed it for several successive seasons, and under a variety of circum- 

 stances, we attribute the fact to the presence of minute fungi, which, by some 

 unknown process, feed upon the cellular tissue, and convert its nutriment- 

 juices to their own use. 



The propagating organs of all the fungi are of extreme minuteness, and 

 discernible only by high magnifying powers. This minuteness of size 

 renders them capable of being readily absorbed by moisture, and conveyed 

 through the roots of plant into the tissues of the other parts. The germi- 

 nation of these organs is effected in the young and pulpy portions of the 

 plant, which abound in starch and sugar, and, on starting into growth, 

 produce a sort of beaded mould similar to the torata, or yeast-plant, which 

 occurs in fermenting liquids. On cutting a thin section of a diseased 

 peach-leaf, traces of this moniliform arrangement of round globules can be 

 seen. It is well known to mycologists that a great variety of developments 

 issue from the same cause, and have hitherto borne in science distinctive 

 terms of appellation, indicating not only separate species, but distinct genera. 



