ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 67^ 



the trees never completely recover. Spraying with a fungicide is recom- 

 mended to growers. 



Notes have been published on the silver leaf disease, found by J. 

 Percival to be due to Stereum purpureum. Experiments carried out at 

 Woburn under the direction of Pickering* have proved the truth of 

 the theory. The disease was induced in healthy trees by inserting a 

 small piece of the fungus in a cut made in the bark. The disease is not 

 always fatal : about one-third of the trees attacked eventually recover. 

 Infected trees should be burnt. 



F. Eulefield f chronicles cases of the death of five-year old pines 

 caused by Rhizina undulata, which grew on the roots and spread from 

 one tree to another through the soil. 



In discussing % the parasitism of fungi, G. Arcangeli records the 

 finding of Fomes lucidus on Gedrus Deodara and on Abies cilicica, both 

 about thirty years old and in a decaying condition. He was doubtful if 

 the fungus were the cause of disease. Another case is given of a tree 

 on which grew Fomes rubriporus, but it had grown there many years 

 without damaging the tree. He cites also the occurrence of Armil- 

 laria mettea growing for years near to some trees which remained un- 

 injured. 



W. 0. Grlover§ records the occurrence in Ohio of apple blotch, a 

 disease caused by the fungus Phyllosticta solitaria. At the time the 

 apples are about to be harvested the blotches are most prevalent, and 

 the pycnidia begin to appear in the diseased spots below the epidermis 

 of the apples. The fungus also attacks the leaves and twigs. Spraying 

 and pruning are both essential for the control of this disease. 



In a leaflet issued by the Board of Agriculture || a description is 

 given of strawberry leaf-spot (SpltsereUa fragarise), a disease of the 

 leaves very common in all parts of the country, and when the injury is 

 severe the yield of fruit may be seriously affected. The writer recom- 

 mends spraying, or, after the fruit is gathered, mowing down the leaves 

 and burning them over the strawberry beds. 



A summary! of the diseases of garden plants is given by J. Lind. 

 In Jutland, where there is much rain and a short summer, many trees 

 are killed by cancer. In Seeland and other isles better conditions prevail, 

 and cancer attacks the fruit-trees only in damp situations. Notes on 

 other diseases are also given. 



R. Laubert ** writes on the most important diseases of the rose, one 

 of which, Coniothyrium wemsdorjise, appears as brown spots on the 

 branches in the early season of the year. The shoots above the parts 

 attacked become enfeebled or die. A Ilotrytis disease attacks the flower- 

 buds, especially in damp hot weather. Peronospora sparsa causes brown 



* Journ. Board. Agric, xviii. (1011) pp. 38-9. 



+ Nat. Zeitschr. Forst.-Landw., viii. (1910) pp. 527-9. See also Ann. Mvcol., 

 is. (1911) p. 202. 



I Atti Soc. Tosc. Sci. Nat., xx. (1911) pp. 13-16. 



§ Ohio Naturalist, xi. (1911) pp. 334-6 (4 figs.). 



I Leaflet No. 243, 2 pp. (1 fig.). 



«[ Gartner Tideride, 1910, pp. 219-:!:.'. See also Bot. Centralbl., cxvi. (1911) pp. 

 569-70. 

 ** Gartenilora, 1910, Heft 5. See also Zeitschr. Pflanzenkr., xxi. (1911) pp. 233-4. 



