244 



JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Cocllin Moth, Spraying- for. By Professor A. B. Cordley (U.S.A. 

 St. Bd, Hi rt. Oregon, Report 1901-2, p. 118; illustrations and tables).— 

 A Ion- and valuable article is here given, the subject being treated most 

 thoroughly. The writer questions the theory that the moth has three or 

 four broods annually. The description and life-history are given, and the 

 effect of temperatures on habits. Descriptions are given of the egg, 

 the lana. and the pupa. Its natural enemies also receive attention. 

 Tables are given showing the relative effects of early and late spraying, 

 \ iews of spraying apparatus at work, and illustrations of Apples and bark 

 attacked by the moth. The conclusions arrived at are, that the codlin 

 moth is the most serious Apple pest ; the eggs are deposited principally 

 on the surface of the fruit, and not in the calyx. Birds are the most 

 effective natural aids in controlling the moth, and spraying with one of 

 the arsenites is the most practical method of protecting the fruit. Persist- 

 ent and intelligent spraying should give 85 to 90 per cent, of fruit trees 

 free from worms. — V. J. M. 



Coffea robusta {Bull. Bot. Dep. Trinidad, No. 38, p. 533 ; April 



1903). — A note in praise of the flavour of this new coffee, which is found 

 to be a productive and good kind for lowland cultivation. — E. A. B. 



Coloured Glasses, Influence of, on the Red and Yellow 

 Pigments in Plants. By Emilo Laurent (Rev. Hort. Beige, xxviii. 

 No. 11, p. 213). — M. Overton showed by experiment that an excess of 

 glucose caused a reddening. The author experimented with Telanthsra 

 versicolor, of a pronounced Ted foliage, in two frames with rel and two 

 with blue glass, and on2 with clear glass, uncoloured. None of the 

 glasses were monochromatic. Under red and blue glass the leaves of 

 normal dimensions were all green ; after a month the leaves were smaller. 



A variety of Golem with large leaves, green at the base and red- 

 violet towards the apex, bore normal leaves under the clear glass, but 

 under the red and blue glasses the leaves diminished in size by degrees, 

 and the coloured parts became more and more reduced. The flowers 

 were green. 



Similar results occurred with species of Perilla, Aitemanthera, and 

 Achyranthes. Zonal Pelargoniums became entirely green under red and 

 blue glasses. 



The result proved that a brilliant light favours the colorisation of 

 foliage, and can easily be shown in purple-leaved trees &c, the colouring 

 matter of Leaves, as of flowers, depending on matters assimilated by the 



leaves. 



Of trees with golden leaves, used in experiments, were the Elder, 

 Spiraea, Byringa, Privet, &c. When badly illuminated such become 

 green. 



Efc 'I glass provoked an etiolation in three species ; but the Elder and 

 Byringa were completely green. 



I'ndcr 1.1 iic ^lass the stems were short, but the leaves of Elder and 

 Syringa were well greened. 



These experiments proved that the yellow pigment, like the red, is 

 also a product of assimilation. — G. H. 



