ABSTRACTS. 



739 



Citrus medica var. dig'itata. By A. Berger (Gard. Ghron. No. 

 814, p. 71, fig. 26 ; Aug. 2, 1902). — One of the most curious varieties 

 belonging to this genus is here figured and described. It grows chiefly in 

 the Chinese province of Fokien. The photograph was taken in Mr. Han- 

 bury's garden at La Mortola, where various species of Citrus grow freely. 

 This variety is more a bush than a tree. The peculiarity of this variety 

 is that the carpels of the fruit are not united at the top, but are developed 

 separately like a number of fingers. The Chinese call the fruit " The 

 fingers of Buddha." Similar digitate fruits occur in other species of 

 Citrus— G. S. S. 



Clover Anthracnose. By 0. Kirchner (Zeit. f. Pflanz. xii. 1902, 

 pp. 10-14 ; 2 figs.). — The author examined more completely this disease 

 described by Mehner in 1901 (see Abstracts, vol. xxvi. p. 916). In two 

 sets of clover plots the disease was worst on a red clover from Northern 

 France, and this seed is regarded as the carrier of the fungus, which 

 spread more or less to other varieties. Fig. 1 shows a plant attacked ; 

 fig. 2 the spore-production. The author considers it distinct from the 

 North American Gloeosoporium trifolii, Peck, and proposes the name 

 G. caulivorum because it causes characteristic depressed spots on the 

 stem, light brown in colour with a black edge, and the conidia are slightly 

 curved.— W. G. S. 



Coffee Culture in Queensland. By Howard Newport (Qu. Agr. 

 Joum. x. p. 389 ; May 1902). — This is the tenth communication upon the 

 subject, and is restricted to topping and suckering, and is therefore strictly 

 cultural as applied to local requirements, by the " Instructor in Coffee 

 Culture."— M. G. C. 



Coloured Glass, Effect on Vegetation of. By G. T. Grignan 

 (Rev. Hort. pp. 388-90 ; August 16, 1902). — Observations regarding the 

 utility of red and blue glass for respectively hastening or retarding growth. 

 He alludes especially to M. Camille Flammarion's experiments and 

 emphasises his warning that much of the effect depends upon the 

 spectroscopic quality of the colour of the glass, which cannot be detected 

 visually with certainty. Hence many reputed failures. Further, it is not 

 suggested that it is beneficial to keep plants permanently under coloured 

 glass : this should only be used temporarily for hastening or retarding, 

 natural white light being essential to continued health. Blue glass keeps 

 vegetation at an absolute standstill as if asleep, even Strawberries 

 remaining thus from May to October. Red or orange, on the other hand, 

 stimulates growth remarkably. — C. T. D. 



Composite, Numerical Variation of the Ray-flowers of. By 



E. M. Wilcox (Bot. Gaz. xxxiii. No. 6, p. 462). — The present paper deals 

 with Helianthus annuus. 1,103 heads were examined, and the number 

 of ray- florets classified and tabulated with a curve between 12 and 28 ; 

 20 gave 80*25 per cent., and 21 70*08 per cent. None of the others were 

 higher than 7*25 per cent. Again, from 29 to 45 there were only three 

 above 34. 



[The author does not allude to phyllotaxis ; but this appears to be 



B B 2 



