COLOR IN FLOWERING PLANTS. 77 



started on his quest with shoes of swiftness, charmed sword, and 

 invisible cloak, may well have been one of Nature's models. 

 Many a time since, the invisible cloak has given the victory to her 

 heroes. In the hand-to-hand battle of life, which is continually 

 waging, many an animal escapes unscathed simply by being so 

 like the objects among which it lives that only the keenest sight 

 can distinguish between them. This is "protective coloring." 

 Walking-sticks resemble twigs ; alligators, floating logs ; brown 

 bitterns, the rocks among which they stand motionless watching 

 for prey; gay birds-of-paradise are almost invisible among the 

 branches of brilliantly blossomed trees. But the phenomenon is 

 not confined to animals. 



A remarkable thing about fruits is the great difference in color 

 between the dry and fleshy kinds. It is hard to think of a con- 

 spicuous dry fruit in all our flora, yet they are far the most 

 numerous ; for, of the eight hundred and eighty-nine genera of 

 flowering plants given in Gray's Manual, eight hundred and nine 

 have dry fruits. But many of the eighty fleshy-fruited genera 

 are brightly colored : ten have white, eight yellow, eight yellowish, 

 thirteen blue, twenty-three (usually shining) black, sixteen purple, 

 twenty-five red species. Only four have no other color than 

 green. 



Surely this is a significant contrast. There is no intrinsic 

 reason why a nut-shell should not be as brightly tinted as a peach 

 skin, but in the light of modern theories of distribution the prob- 

 lem is simplified. It is now known that dry fruits are dissemi- 

 nated by purely mechanical means, by the agencies of wind and 

 water, or by the unconscious help of animals to whose hair, 

 feathers, or feet they adhere. But fleshy fruits are largely, often 

 entirely, dependent upon animals which eat the attractive and 

 palatable covering, and in one way or another scatter the un- 

 injured seeds. As there are wind, water, and insect pollinated 

 flowers, so there are wind, water, and animal carried fruits ; and 

 the first two classes of both are inconspicuous, the third common- 

 ly beautifully adorned. The negative reason, then, for the absence 

 of color among dry fruits is the needlessness of attractive charac- 

 ters; but there is a positive and perhaps as powerful a cause 

 which has operated to the same end. Dry fruits are by no means 

 unpalatable. The staple vegetable foods, sought after alike by 

 the lower animals and by man, are grains, legumes, and nuts. In 

 their great popularity is their great danger ; their treasure must 

 be hidden. The seeds of many Composites, greedily eaten by birds, 

 are therefore covered ; the distasteful or even poisonous fruits of 

 the parsley family freely exposed. The hard shells of nuts, the 

 hairy or bristly coverings of many pods, defeat the attacks of 

 numerous foes. But the charmed bodies of Siegfried and Achilles 



