Variegated Leaves. 267 



cation of something new but as a reminiscence of times 

 long past when these varieties were in general favor. 



Variegation is classified under several headings. In 

 the first place there are the yellow and the white varieties. 

 In the former the chlorophyll is only insufficiently pro- 

 duced, but in the latter even the xanthophyll or carotin 

 is lacking;^ and a more or less abortive development of 

 the chloroplasts is usually correlated with the absence 

 of these pigments.^ 



Further we distinguish marginate, flecked and striped 

 sorts. The former seem to constitute a variety for them- 

 selves and are much rarer than the latter ; they appear to 

 be good races, that is, to be as constant as any ordinary 

 garden, variety, but I shall have little to say about them 

 in this part. The most characteristic and best known 

 example of them is the white bordered holly to which 

 we have already referred."^ 



Whether a plant is flecked or striped depends as a 

 rule on the mode of venation of the leaves. Many varie- 

 gated monocotyledons have striped leaves {Agave, Con- 

 vallaria luajalis, Phoriniiun tenax, Tradescantia re pens, 

 etc.) whereas the dicotyledons are usually flecked or 

 streaked. 



The incomplete development of the chloroph}ll ob- 



^ See T. Tammes, Ueber Carotin, Flora, 1900. 



^For further information on this point see the elaborate ana- 

 tomical studies of A. Zimmermann, Ucber die ChromatopJwrcn in 

 panacJiirtcn BlUttcrn, in Beitrage zur Morphologie und Physiologie 

 der Pflanzenzelle, Heft II, 1891, pp. 81-111, and Ber. d. d. hot. Ges. 

 VIII, 1890, p. 95. Also H. TiMPE, Beitrage cur Kcnntniss dcr 

 Panachining, Inaug.-Diss., Gottingen, 1900. 



* Marginate forms are commonly supposed by gardeners to be 

 more stable than flecked ones. This fact was noted by Morren in 1865. 

 (Hercditc de la panachure, Bull. Acad. roy. Belg., T. XTX. 2d series, 

 p. 225). Verlot however maintains the opposite opinion (Dcs J\vtc- 

 tes, 1865, p. 74). For information relating to variegated varieties of 

 Ilex see Focke, Abh. d. Naturw. Ver. zu Bremen, Vol. V, pp. 401-404- 



