310 Oxydases and Pigments of Plants 



DESCRIPTION OF PLATE XIX. 



The illustrations are reproduced from water-colour drawings by Miss D. Richardson 

 from natural flowers (Nos. 1, 3, 10 and 13) and from preparations made by treating 

 the flowers with reagents for oxydases (see text). 



1. A uniformly (self) coloured blue flower (natural colour). 



2. The same after decolourisation with the benzidine reagent and subsequent treatment 



with hydrogen peroxide ; showing epidermal and bundle peroxydases. 



3. A white-flowered form (natural). 



4. A recessive white (a-naphthol and H2O2); showing bundle peroxydase. 



5. A recessive white (benzidine and H2O2) ; showing epidermal and bundle peroxydases. 



6. A dominant white (benzidine and H2O2). 



7. A dominant white (treated first with carbon dioxide, then with benzidine, and sub- 



sequently with H2O2). Cf. with 6. 



8. A dominant white treated with hydrogen cyanide — benzidine — H2O2 . Cf . with 6. 



9. A dominant white treated with HCN, a-naphthol H2O2. 



10. A blue with white inhibitory patches (54/2/1). F^ of cross between Cambridge blue 



and Snow King (natural colour). 



11. The same after decolourisation with the a-naphthol reagent and subsequent treatment 



with H2O2 . 



12. Another flower of 54/2/1 after decolourisation with the benzidine reagent and subse- 



quent treatment with H2O2 . 



13. A heterozygous plant of the same race (54/2/1) natural colour. 



14. The same after decolourisation with the benzidine reagent and subsequent treatment 



with H2O2. 



REFERENCES. 



1883. Pick, H. "Ueber die Bedeutung des rothen Farbstoffes bei den Phanero- 



gamen u. die Beziehungen desselben zur Starkewanderuug." Bot. Centhl. 



1883, Vol. XVI. 

 1904. Durham, Florence M. " On the Presence of Tyrosinases in the Skins of 



some Pigmented Vertebrates — Preliminary Note." Proc. Roy. Soc. 1904, 



Vol. Lxxiv. p. 310. 

 1906. Bateson, W., Miss E. R. Saunders and R. C. Punnett. " Reports to the 



Evolution Committee, Royal Society, London." Report III, p. 18. 

 (See also Report /, 1902.) 

 1908. Palladin, W. " Die Verbreitung der Atmungschromogene bei der Pflanzen." 



Ber. d. Bot. Oes. 1908, Vol. xxvi. p. 378. 



1908. . " Die Bildung der Atmungschromogene in der Pflanzen." Ihid. 



p. 389. 



1909. Hurst, C. C. " Inheritance of Albinism in Orchids." Gard. Chron. 1909, 



Vol. XLV. p. 81. 

 1909. Kastle, J. H. " The Oxidases." U. S. Treasury Dept. Hygienic Laboratory. 

 Bulletin, No. 59, December 1909. 



