Zöology; a textbook for colleges and universities . Thedark color of the disk florets, as well as the specklingon the stem, is caused by a coloring matter called antho-cyanin, dissolved in the cell sap. Anthocyanin (fromGreek words meaning flower-blue) is a name for a classof pigments which may be pink or blue, and when ex-tracted may often be changed from one color to the 54 ZOOLOGY Red sun-flower dueto an ex-tension of anthocyanin already present other by chemicals. The acid state is pink, but whenan alkali is introduced the solution may become anthocyanin of the sunflower turns gre
Zöology; a textbook for colleges and universities . Thedark color of the disk florets, as well as the specklingon the stem, is caused by a coloring matter called antho-cyanin, dissolved in the cell sap. Anthocyanin (fromGreek words meaning flower-blue) is a name for a classof pigments which may be pink or blue, and when ex-tracted may often be changed from one color to the 54 ZOOLOGY Red sun-flower dueto an ex-tension of anthocyanin already present other by chemicals. The acid state is pink, but whenan alkali is introduced the solution may become anthocyanin of the sunflower turns green in alkali,but this is probably due to the presence of a yellowsubstance (flavone). 6. The first sunflower with red (maroon) on the raysseems to have been observed in South Dakota in 1892,but no record was made of the fact at the time. In1910, in Boulder, Colorado, a plant was found by theroadside, having the rays strongly suffused with chest-nut red. This was an example of the prairie speciesor race, and had not come from a cultivated FIG. u. The red sunflower (Helianthus annuus, variety). THE RED SUNFLOWER 55 The red color was the same anthocyanin as occurs in thedisk of these sunflowers, only greatly increased inamount and extending over the rays. The coloringmatter was really pink, but the effect on an orangebackground was chestnut. It was an astonishing thingto see a style of coloration entirely new to Helianthus,though well known in some allied plants, and due notto any new substance, but to an increase of one com-mon in sunflowers. Thus does Nature produce novel-ties, by taking advantage of what exists. Man, notingthe process, may in certain respects follow her he cannot produce variations, he can at least oftencombine them, and the combinations will be in everypractical sense new forms. 7. The Boulder variety with reddened rays existed Red sun-in 1910 as a single plant. Since sunflowers are sterile Jt°Jodd>rwith their own pollen, it could be p
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