NOTES AND ABSTRACTS. 



103 



as the plants are commencing to flower. The roots of the affected plants 

 are discoloured and contain a large amount of the mycelium of a fungus 

 with pinkish coloured spore masses. This disease appears to be a soil 

 one, and difficult to control. Asters should not be grown in infected 

 ground for at least two years, otherwise some powdered sulphate of iron 

 should be worked into the soil some weeks before the plants are set out. 



M. C. C. 



Astrantia, Biometrieal Researches on. (Beih. Bot. Centralbl, 

 xxiv., Erste Abth., Heft 1, pp. 1-19). — Herr Paul Vogler of St. Gall gives 

 some detailed researches dealing with the number of bracts, of flowers, 

 and of male flowers in A. major. — G. F. S.-E. 



Beet Sugar Industry, Progress of, in 1906. By C. F. Taylor 

 {U.S.A. Dep. Agr. Beport 84; May 1907). — Gives a great amount of 

 valuable information concerning the progress in securing greater sugar 

 yield and statistics relating to the area under cultivation of this crop 

 in the different States. It is -pointed out that beet sugar growing is 

 productive of great good to agricultural interests in many directions. 



F. J. G. 



Begonia manicata. By Ad. van der Heide (Le Jardin, vol. xxii. 

 No. 516, p. 244 ; August 20, 1908 ; 1 fig.). — A plea for an old and almost 

 forgotten species introduced from Mexico in 1840. Handsome window 

 plant, with large characteristic leaves, adorned like the petioles with 

 long red hairs, which form a sort of gauntlet, and give the plant its 

 name. Abundant rose-coloured flowers. There is also a white variety, 

 B. m. alba, and a fine variegation B. m, aurea maniculata. It thrives 

 in the winter garden or conservatory, little or no heat being required, 

 although rich 'soil and plenty of water are essential. Propagation, like 

 other Begonias, by cuttings of leaf or shoot. — F. A. W. 



Begonia Patria. (Le Jardin, vol. xxii. No. 517, p. 258 ; September 5, 

 1908). — A cross obtained by M. Lemoine from B. socotrana x B. Pearcei. 

 It resembles B. Gloire de Lorraine, but forms a more vigorous plant 

 with brighter inflorescence. The flowers are magnificent — scarlet, salmon, 

 and copper, with golden under-surface — and are very persistent, lasting 

 unimpaired for more than a month after full development. A plant only 

 25 c. in height will often carry several hundred blossoms. — F. A. W. 



Botrytis cinerea, Observations on the Biology of. By F. T. 



Brooks (Ann. Bot., xxii., July 1908, p. 479-437). — Experiments were 

 conducted with the well-known parasitic fungus Botrytis cinerea and 

 the lettuce plant. Botrytis conidia were unable to infect healthy green 

 leaves, neither could they infect plants (grown in artificial cultures) 

 weakened by the omission of one or other of the essential elements. On 

 the other hand conidia were capable of infecting wounded leaves just 

 beginning to turn yellow. 



Though conidia have no effect on healthy leaves, if young mycelium 

 nourished saprophytically is placed on such leaves infection occurs at once 

 and the fungus spreads rapidly. 



