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however, Mr. ORTON found that they had been infected with the disease in many places, possibly hundreds of times, but were actually resistant and had grown on and overcome or thrown off the disease. Here then in these resistant plants we have the starting point for the production of resistant strains. By selecting seed for reproduction from these resistant plants we can doubtless in a few years breed up numerous strains sufficiently resistant to the disease to be practical for general culture. One test of the kind has already been made by Mr. ELIAS L. RIVERS* of James Island, S. C., a planter who has been co-operating with the Department in work on this disease. Mr. RIVERS last year collected seed from several resistant plants in a badly diseased field of Sea Island cotton and this year the seed was planted in a single row through a badly infested field, with ordinary Sea Island on each side. The row of cotton grown from this seed proved to be remarkably resistant, hardly a single plant showing any marked injury from the disease, while almost every plant of the ordinary Sea Island in adjoining rows were killed. [A photograph was exhibited showing this remarkable effect.] It should be remembered that this is the result of simply one year's selection, and a selection in which the immunity of the male parent was not considered. If, coupled with this selection of seed from resistant plants, the work had been started earlier in the season and flowers of resistant mother plants had been hand crossed with pollen from similar resistant plants, it is probable that a still greater and more lasting effect would have been obtained. This year the work is being done in a more careful, systematic way, and we are encouraged to believe that the disease may be entirely controlled in this manner.

Another line of cotton improvement work which is being investigated by the Department is the production of new and different varieties from those now existing. We are not satisfied to simply improve the strains that already exit, but desire to produce new ones. I am not certain whether it will meet your

* See paper on Sea Island Cotton by ELIAS RIVERS. Transactions New England Cotton Manufacturers' Association, Volume 59, page 244.

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Improvement of Sea Island Cotton by selection: O, O, Ordinary Sea Island CottonOriginal Type from which selection was made; S, S, Selected Sea Island Cotton, showing increased length of Fibre. (7-8 natural size.)

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Seeds of Klondike, Sea Island, and Ordinary Upland Cotton: 1 and 2, Seeds of Klondike with and without lint; 3, Seeds of Sea Island Cotton 4 and 5, Tufted Seeds of Ordinary Upland Cotton (the variety from which the Klondike was developed), with and without lint. (13-16 natural size.)

FIG. 3.

Seeds of hybrid cotton and its parents, with the fibre pulled out to show the relative lengths and amounts: M, Fibre of Sea Island Cotton, male parent; F, Fibre of Upland Cotton, female parent; H, Hybrid between them. (10-11 natural size.)

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Bolls of Hybrid Cotton and its Parents: M, boll of Klondike (a variety of Upland Cotton), male parent; F, boll of Sea Island, female parent; H, boll of hybrid between them, showing increased size. (5-7 natural size.)

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Bolls of Hybrid Cotton and of its Parents: M, boll of Klondike (a variety of Upland Cotton), male parent; F, boll of Ashmouni (a variety of Egyptian Cotton), female parent; H, boll of hybrid between them, showing increased size. (5-7 natural size.)

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