250 



be associated with chemical and physical changes that occur. 

 In many of these the color changes develop according to the age 

 of the leaves. 



Turning one's attention to the red and the blue colorations, 

 we note also a great diversity in the amount of color, in its 

 quality and intensity, and in the arrangement in patterns. While 

 these pigments are made by plants their development is greatly 

 influenced by such external agents as light. There is also much 

 variation from bright crimson to dark blue according to the 

 relative acidity or alkalinity of the sap. But whether a plant 

 will be almost solid red, as the garden beet, or have only red 

 blotches on the leaves, or not be red at all, is chiefly a matter 

 of the hereditary nature of the plant. 

 / The gFOttp-ef red, blue, and violet pigments that g'lxe such 



brilliant colors in leaves are d«e~taT;he same pigments as ,theT(5r 

 responding colors in flowers and fruits and the colors that develop 

 in the autumnal coloration of the foliage of our deciduous trees. 



The gayest colorations and most fantastic patterns in the 

 foliage of ornamental plants are those where loss of green with 

 various developments of yellow occur along with red and blue 

 pigments. In these, a shade of red in yellow areas produces an 

 effect quite different from that when it is in green areas. This 

 is well illustrated in the crotons with their fantastic combinations 

 of green, yellow, and various shades of red, with also marked vari- 

 ations according to the age of the leaves. A large and extremely 

 varied collection of these plants may be seen in the main green- 

 houses near the entrance from the Third Avenue elevated 

 railway. (A group of these plants was included in the collection 

 of variegated plants assembled for display in connection witli 

 the lecture.) 



In propagating plants with ornamental foliage, it is to be 

 remembered that man>' of them do not breed true from seed. 

 This is especialh- true of the green and white (or \ellow) varie- 

 gations, both blotched and white-bordered. It is also the case 

 for many patterns of red colorati(jn. These plants are very 

 generally proi)agated vegetatively by such means as cuttings. 

 In thiswav the numerous ornamentals, such as the white-bordered 

 geraniums and pelargoniums and the red-blotched or solid-red 

 types of ("oleus, may be kept rather constant to type in garden 

 or pot culture. A. B. Stout. 



