Chemisch-pharmaceut. Botanik. — Agricultur u. Horticultur. 287 



It is to these substances that the yellow colour of flowers, autumnal 

 leaves and iruits is mainly dne. 



Certain other yellow pigments soluble in water and alcohol, bnt 

 insoluble in Carbon bisulphide must be removed beiore examining the 

 xanthophylls. 



The alcoholic extracts of twenty common yellow flowers were 

 examined. The xanthophyll was taken np with Carbon bisulphide and 

 three distinct yellow pigments were found to be present distinguishable 

 by their spectra. 



These Schunck provisionally terms L-, B-, and Y-xanthophyll. 

 The spectrum oi each shows three bands between the solar lines F. and 

 H., and compared with chrysophyll, a substance forming small red crystals 

 irom concentrated alcoholic extracts oi green leaves the bands show a 

 product shiiting towards the v'i'olet, those oi chrysophyll being the least 

 reirangible, and those oi Y-xanthophyll the most so. The effect of acids 

 on these substances differs and serves as the best method of distinguishing 

 them. In contradistinction to the B. and Y, the L-xanthophyll is more or 

 less stable in alcoholic Solution, but little change being apparent even 

 after the lapse of several weeks when kept from the light. 



In foliage-leaves the yellow colouring matters accompanying Chloro- 

 phyll are chrysophyll, L- and B -xanthophyll and the pigment formed 

 from the latter by the action of acid, in addition to the other set of 

 pigments insoluble in Carbon bisulphide mentioned above. 



The etiolated leaf of the daffodil shows the same xanthophylls, but 

 no chrysophyll. 



In the autumnal leaf are found L-xanthophyll and the acid derivative 

 of B-xanthophyll greatly preponderating over B-xanthophyll itself. 



In the rhind of the Orange the pigments insoluble in Carbon 

 bisulphide are in great excess. In addition chrysophyll and the acid 

 derivatives of B- and Y-xanthophyll are found. 



The pigments of Lemon-peel are similar but very little chrysophyll 

 is present. 



The Carotin of Carrots appears to be very nearly identical with 

 chrysophyll. 



A hitherto undescribed pigment for which the author proposes the 

 name Lycopin is found as the principal colouring matter of the tomato- 

 fruit. The spectrum shows three bands considerably less refrangible 

 than those of chrysophyll. 



From the seeds of Bixa Orellana (Annatto) a pigment, bixin, 

 crystallising as red brown flockes can be extracted with boiling alcohol. 

 Its spectrum closely resembles that of chrysophyll, but differs in the 

 three bands being less refrangible though more so than those of 

 lycopin. 



Judging from its spectrum the yellow lypochrome, or lutein of the 

 yolk of egg, and of the fowl's serum, appears to be identical with 

 L-xanthophyll. E. Drabble (London). 



Thouvenin, JH., Precis de Microchimie vegetale. Vol. I. 



Paris, Doin ed., 1904. petit in-8. 100 pp. Avec 22 desslns 



dans le texte. 



Petit ouvrage destine aux debutants micrographes, donnant 

 une serie de conseils pour la coloration et la caracterisation du 

 contenu cellulaire et aussi de membranes. L'ouvrage se ter- 

 mine par un expose des methodes de preparation de quelques- 

 uns des reactifs les plus usites. E. Perrot. 



A. B. C. ofCotton Planting(compiledby officers of 

 the Imperial Department of Agriculture for the 

 West Indiesi. Pamphlet Series No. 31. 



