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effort to bring it early under control, before the soil or neglected 

 gardens become abundantly supplied with spores, and thereby 

 sources of infection. 



As a lesson for us, the experience of the old world may be very 

 useful. The Hollyhock Rust in question appeared in Europe 

 about 1869, spread over England and the continent in a few years, 

 increasing to such an extent that the cultivation of the choice va- 

 rieties of these beautiful flowers entirely ceased in many localities, 

 thus entailing great losses, the magnitude of which, in the aggre- 

 gate, was never fully known. 



It affects the host-plant after this manner : In places where it 

 has become established it appears in May and June on the leaves, 

 stems and petioles of the host, having apparently wintered on the 

 radical or root leaves. Externally it is seen in spots or sort, (see 

 figure,) which are yellow at first. As seen on the under side of 

 the leaf, they soon become wart-like and brown, or even gray, and 

 consist wholly of two-celled spores. These sori, and the myceli- 

 um within the leaf from which the sori spring, may so increase as 

 to cause the leaf to wither, dry up and appear as if scorched by 

 fire, long before the time for the appearance of the flowers. In- 

 deed, in many cases no flowers ever appear. Where the attack is 

 not severe, these sori may remain and the leaves continue green 

 until the latter fall in the autumn. 



Several remedies for the disease were at last found effective by 

 European growers, and that given in the Gardener' 's Chroniele for 

 1874, p. 243, is added below : 



Permanganate ot Potash, (Sat. Sol.), ... .2 Tablcspoonfuls. 

 Heater, / Quart. 



Apply to the spots and all diseased parts with a sponge, and not a 

 syringe or sprayer. The remedy is cheap and easily obtained. 



It has been thought that the disease cannot endure severe win- 

 ters. The present promises to be unusually cold, and we shall 

 watch its effect on the Rust. If the prevalence of the Rust 

 in the spring demands it, a resume of what is known concerning 

 it will be published. Will each one interested, and acquainted 

 with the disease send us a note of its severity in known localities, 

 accompanied, if convenient, with a small specimen of a diseased 

 leaf? Also, will each add the date of its first appearance in the 

 places cited, as we shall be glad to know of its progress westward, 

 and present geographical distribution in America. 



WILLIAM R. DUDLEY. 



