The Peckhams relate that, having placed some red nasturtiums upon a yellow background near a wasps' nest, they saw that the insects flew to the flowers before their return to the nest, while they passed by indifferently when clear yellow nasturtiums were sub-stitued for the red ones. "And, since the odor was equally strong in both cases, it seems indeed that the color was the sole agent of attraction." Plateau himself recognized the demonstrative value of this experiment.

The bees in search of dainties visit equally gaudy colors. This Lovell (1912) observed with some workers which had become accustomed to take honey from a gray carton ; the appetite once appeased, they left on their expedition, entered flower gardens in the neighborhood, and always chose the most brilliantly colored flowers.

The horminelle sage is a large, decorative labiate, which carries at its tip a splendid bouquet of blue or rose bracts and, below, whorls of apparently small flowers. Having observed that the honey-seeking insects went customarily to the flowers and not to the terminal bunch, Plateau (1898) concluded that the lively coloration did not serve as a guide to the honey-collectors. However, certain of them went first to the conspicuous blooms, and those were surely apprentices. The insects should have been followed from the instant they began to frequent the sage. With similar inflorescences isolated in the field, we reach quite different results. Ferton saw Andrena vetula visiting the feather hyacinth (Muscari toupet) whose sword-like inflorescence is composed of little fertile flowers of a pale violet and terminates in a group of sterile flowers whose violet hue is magnificent. The bee collects from the fertile flowers, which alone contain nectar; but how does it comport itself in the presence of plants from which all of these flowers have been taken away? "When Andrena vetula came to one of these mutilated inflorescences," says Ferton, "it flew toward the plume, but when it was some centimeters away it descended to the place where the fertile flowers belonged and, not finding them, it went to another plant." The same biologist has seen other Andrenas visit the white mucons patches (frog spittle) produced by a little cicadel-lid. From this the fair conclusion is that in a richly beflowered space the bees are "better guided by sight than by perfumes which are being given out at the same time by all the plants. ' '

The experiments of Josephine Wery (1904) are no less demonstrative. They were carried on in a bare field where, five-hundred centimeters from a bee-hive, were placed bouquets or food to which the bees came, not by chance, for no other flower could distract them, but by the sole attraction of the colors or of the perfume. I repeat here some of the results obtained by this observer:

(1) Natural flowers, uncovered (balsam, coreopsis, etc.), 32 visitors.

The same, hidden by leaves, 7 visitors.

(2) Flowers with slight odor but highly colored (dahlia, etc.), 35 visitors.

Very odoriferous flowers but slightly colored (Reseda), 6 visitors.

(3) Whole flowers and, at six yards, honey in a beaker :

Whole, free flowers, 32 visitors ; honey, none. Whole flowers under glass, 12 visitors ; honey, none.

(4) At intervals of six yards exposed natural flowers, the same hidden under leaves, honey, and artificial flowers :

Natural, exposed flowers, 25 visitors. Hidden flowers, 7 visitors. Honey, 1 visitor. Artificial flowers, 20 visitors.

Carried on with' innumerable extraordinary precautions, these-experiments led, as we see, always to the same result.

Plateau (1876) has denied the vexillary role of artificial flowers. In a garden filled with different flowers, where Arabis alpina was "nearly the only one visited by insects," he introduced very vivid artificial flowers* and found that they received no visits. The contrary would have been surprising, since apparently the insects neglected all the natural flowers with the exception of the Arabis, and from this experiment together with several other similar ones Plateau could not but conclude that artificial flowers do not attract insects.

The same author describes also an observation by Vallete, who saw a day sphinx {Macroglossa stellatarum) try its beak upon flowers painted on tapestry. Although J. Wery, in her memoir, reports several similar facts mentioned by different biologists, and although Perez confirms this observation with another very similar one, the subject surely needs more careful study.

But, if we except this special case, it is quite correct to say that anthophilous insects are guided to flowers by the coloration which the latter present, and that, all things being equal, they visit those which stand out by their colors against the green foliage of the plants.