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The Museum Gazette 



during the winter months. You will find C. rugosa (in modern termi- 

 nology, C. bidentatd) equally common on the trees, it is smaller and 

 thinner than C. laminata. B. obscums is a short, stout little shell, 

 seldom exceeding 9 millimetres in height. 



Gardener. Diseases of the Cultivated Chrysanthemum. — At the 

 present time three diseases are recorded for this country, viz., sclero- 

 tium disease {Sclerotinia sclerotiorum, Massee) ; corticium disease 

 {Peniophora chrysanthemi, C. B. Plowright), and the only too familiar 

 Rust (Puccinia hieracii, Mart). The sclerotium, which first appears 

 as a white mould on the stem just above the ground, forms black 

 lumps within the stem. The stem becomes very brittle and falls. 

 From the black nodules in the following spring, small funnel-shaped 

 brownish fungi with long, weak, dark stems appear. The spores 

 from these settle upon dead organic matter, forming an abundant 

 mycelium which ultimately attacks the base of the stems of chrysan- 

 themums. It is said that fresh stable manure favours the spread of 

 the disease. Diseased stems should be carefully collected and 

 burnt. 



The corticium disease also appears on the lower part of the stem, 

 forming a white growth in autumn ; Dr. Plowright, who first dis- 

 covered it, says it resembles a splash of whitewash. It is not con* 

 fined to the stems but extends into the adjacent soil. Diseased 

 plants are shorter in height and thinner in the stem than healthy ; 

 they always die within the year. This disease has hitherto been 

 observed only at King's Lynn in Norfolk, but it is very possible it 

 occurs in other parts of the country. Dr. Plowright remarks that the 

 only treatment is burning the diseased plant. It is useless to 

 separate the apparently healthy shoots. 



The well-known chrysanthemum rust first appeared in 1897, and 

 spread with great rapidity in the very dry summer of 1898. The 

 snuff-coloured uredo spores (summer form) are familiar to all culti- 

 vators of chrysanthemums. This fungus occurs on many wild plants 

 l of the order Composites, notably the hawk-weeds {Hieraciuni). All 

 (diseased plants should be burnt. The disease may be prevented by 

 spraying the new leaves with potassium sulphide solution. 



It is to be hoped that the chrysanthemum leaf blight {Cylindro- 

 sporium chrysanthemii), which has caused so much damage to culti- 

 vated plants in Ontario, Canada, will not find its way into this 

 country. It forms large dark patches on the leaves, which turn yellow 

 and hang down ; the flower buds do not expand. It is stated that 

 fungicides are useless. 



