flowers are wind-pollinated and nectarless, but are visited by bees for pollen. Richter states that one of his apiaries was located near 5000 olive trees, but that he never saw more than two or three bees on the bloom of any one tree, and they were gathering pollen.

POPPY (Papaver). — The poppies with their brilliantly colored scarlet or purple petals are conspicuous both in gardens and fields. All the species are pollen-flowers, and the abundant pollen is very attractive to bees.

Opium poppy (P. somniferum) is cultivated in Europe and Asia for its seed-vessels, from which opium is extracted. There have been reports of bees, while gathering nectar from poppies, becoming stupefied and lying for some time helpless on the ground. An acre of poppies would not yield a drop of nectar; and repeated observations show that bees visit the bloom without injury. A honeybee, which had alighted on a newly opened blossom in which the anthers were still closed, was seen to search unsuccessfully at the base of the petals for nectar.

PLANTAIN (Plantago). — Indian wheat (Plantago ignota) is abundant over vast areas of sandy and gravelly mesas in Arizona. It is one of the principal forms of vegetation, and affords valuable pasturage to cattle. On the deserts it seldom grows more than 5 or 6 inches tall. The silvery-hairy leaves have a grayish appearance, and it is difficult to determine at first glance whether the plants are alive or dead. The flowers are entirely nectarless and are visited by bees for pollen only. On the slopes another plantain (P. aristata), is also very common. None of the plantains, of which there are about 200 species, yield nectar, although several of them have sweet-scented flowers. Honeybees gather pollen from a part of the species. Hovering in the air the bee moistens the pollen with nectar gathered elsewhere, and then brushes it off the anther with the tarsal brushes of the forefeet. Plies are very frequent visitors. The plantains are pollinated both by insects and the wind. (Pig. 11.)

POPLAR (Populus). — Aspen. Cottonwood. The poplars bloom in early

spring, long before the leaves appear. The staminate and pistillate flowers are on different trees, and pollination is effected by the wind. The anthers are purple, and expel the - pollen forcibly, which on mild days is gathered by bees. There are nectar-glands at the base of the leaf-stalks. Honey-dew is gathered from the foliage. Along the rivers of the western plains the narrow-leaved cottonwood and the broad-leaved cottonwood are the common trees instead of the maple, elm, and oak. The narrowleaved cottonwood (P. angustifolia) yields a bright reddish gum, which the bees collect in large quantities and use as propolis. Much propolis is also collected from the balm of Gilead (P. balsamifera). Well-known species are the American aspen, the balsam poplar, the white poplar and the narrow-leaved cottonwood. (Fig. 12.) The poplar should not be confused with the tulip tree, often called tulip poplar.

RAGWEED (Ambrosia artemisiifolia).—Homely weeds, very common in old fields, blooming in autumn and pollinated by the wind. Ragweed belongs to the Compositae. The stamens and pistils are in separate flowers and in separate heads; but both kinds of heads occur on the same plant, the staminate in long spikes, and the pistillate in clusters of two or three in the axils of the leaves. The flowers are green. As a source of pollen in autumn, ragweed is sometimes of value.

ROCK-ROSE (Helianthemum canadense). — Woody herbs with large, solitary, yellow pollen-flowers, and also flowers without petals in clusters. The species are widely distributed.

ROSE (Rosa). — The rose as a pollen-flower is described in “The Flower and the Bee” as follows: “Even beekeepers generally believe that bees gather nectar from wild roses. There has been some discussion of late, writes one of them, as to whether bees get any honey from roses. 'I believe that I have seen them working freely on wild roses, and I see no good reason why roses should not yield honey, as they belong to the same family as the apple, pear, plum, cherry, and raspberry.