WILD FLOWERS [205]
to save it from small bees and flies. It falls out, therefore, only when the bee is in the right position to receive it for export to another foxglove's stigma. Hairy footholds on anthers and filaments are provided lest the bee fall while reversed and sifting out the pollen.
The FERN-LEAVED or LOUSEWORT FALSE FOXGLOVE (D. pedicularia; G. pedicularia of Gray) - a very leafy species found in dry woods and thickets from the Mississippi and Ontario eastward to the Atlantic, north and south, has all its leaves once or twice pinnatifid, the lobes much cut and toothed. It is a rather sticky, hairy, slender, and much branched plant, growing from one to four feet tall; the broad, trumpet-shaped, yellow flower, which is sticky outside, measures an inch or an inch and a half long, and is sometimes almost as wide across. "The most abundant visitor, and the one for which the flower is most perfectly adapted," says Professor Robertson, "is Bombus Americanorum. This bee always turns head downwards on entering the flower. When it enters, or backs out, the basal joints of its legs strike the tips of the anther-cells, when the pollen falls out. I had often wondered why this bee turned upside down to enter the flower.... I discovered that the form of the flower requires it. The modification which requires the bees to reverse is associated with the peculiar mode of pollen discharge. Smaller bumblebees and some other bees which never or rarely try to suck hang under the anthers and work out the pollen by striking the trigger-like awns. They reverse of their own accord, since they are so small they are not compelled to do so on account of the form of the flower. The tube is large...so that most bumblebee workers could easily reach the nectar if the tube were not curved in the opposite direction from that of most flowers, and if the anthers did not obstruct the entrance." Sometimes small bees, despairing of getting into the tube through the mouth, suck at holes in the flower's sides, because legitimate feasting was made too difficult for the poor little things. The ruby-throated hummingbird, hovering a second above the tube, drains it with none of the clown-like performances exacted from the bumblebee. Pilfering ants find death as speedy on the sticky surfaces here as on any catchfly.
GREATER BLADDERWORT; HOODED WATER-MILFOIL; POP-WEED (Utricularia vulgaris) Bladderwort family
Flowers - Yellow, about 1/2 in. across, 3 to 20 on short pedicels in a raceme at the top of a stout, naked scape 3 to 14 in. high. Calyx deeply 2-lobed; corolla 2-lipped, the upper lip erect, the lower lip larger, its palate prominent, the lip slightly 3-lobed, and spurred at the base; 2 stamens; 1 pistil; the stigma 2-lipped. Leaves: Very finely divided into threadlike segments, bearing little air bladders. Preferred Habitat - Floating free in ponds and slow streams, or rooting in mud. Flowering Season - June-August. Distribution - Throughout nearly the whole of North America, Cuba, and Mexico. Europe and Asia.
Here is an extraordinary little plant indeed, which, by its amazing cleverness, now overruns the globe - one of the higher order of intelligence so closely akin to the animals that the gulf which separates such from them seems not very wide after all. In studying the water-crowfoots (q.v.) and other aquatic plants, we learned why submerged leaves must be so finely cut; but what mean the little bladders tipped with bristles among the pop-weed's threadlike foliage? Formerly these were regarded as mere floats - a thoughtless theory, for branches without bladders might have been observed floating perfectly. It is now known they are traps for capturing tiny aquatic creatures: nearly every bladder you examine under a microscope contains either minute crustaceans or larvae, worms, or lower organisms, some perhaps still alive, but most of them more or less advanced toward putrefaction - a stage hastened, it is thought, by a secretion within the bladders; for the plant cannot digest fresh food; it can only absorb, through certain processes within the bladder's
The FERN-LEAVED or LOUSEWORT FALSE FOXGLOVE (D. pedicularia; G. pedicularia of Gray) - a very leafy species found in dry woods and thickets from the Mississippi and Ontario eastward to the Atlantic, north and south, has all its leaves once or twice pinnatifid, the lobes much cut and toothed. It is a rather sticky, hairy, slender, and much branched plant, growing from one to four feet tall; the broad, trumpet-shaped, yellow flower, which is sticky outside, measures an inch or an inch and a half long, and is sometimes almost as wide across. "The most abundant visitor, and the one for which the flower is most perfectly adapted," says Professor Robertson, "is Bombus Americanorum. This bee always turns head downwards on entering the flower. When it enters, or backs out, the basal joints of its legs strike the tips of the anther-cells, when the pollen falls out. I had often wondered why this bee turned upside down to enter the flower.... I discovered that the form of the flower requires it. The modification which requires the bees to reverse is associated with the peculiar mode of pollen discharge. Smaller bumblebees and some other bees which never or rarely try to suck hang under the anthers and work out the pollen by striking the trigger-like awns. They reverse of their own accord, since they are so small they are not compelled to do so on account of the form of the flower. The tube is large...so that most bumblebee workers could easily reach the nectar if the tube were not curved in the opposite direction from that of most flowers, and if the anthers did not obstruct the entrance." Sometimes small bees, despairing of getting into the tube through the mouth, suck at holes in the flower's sides, because legitimate feasting was made too difficult for the poor little things. The ruby-throated hummingbird, hovering a second above the tube, drains it with none of the clown-like performances exacted from the bumblebee. Pilfering ants find death as speedy on the sticky surfaces here as on any catchfly.
GREATER BLADDERWORT; HOODED WATER-MILFOIL; POP-WEED (Utricularia vulgaris) Bladderwort family
Flowers - Yellow, about 1/2 in. across, 3 to 20 on short pedicels in a raceme at the top of a stout, naked scape 3 to 14 in. high. Calyx deeply 2-lobed; corolla 2-lipped, the upper lip erect, the lower lip larger, its palate prominent, the lip slightly 3-lobed, and spurred at the base; 2 stamens; 1 pistil; the stigma 2-lipped. Leaves: Very finely divided into threadlike segments, bearing little air bladders. Preferred Habitat - Floating free in ponds and slow streams, or rooting in mud. Flowering Season - June-August. Distribution - Throughout nearly the whole of North America, Cuba, and Mexico. Europe and Asia.
Here is an extraordinary little plant indeed, which, by its amazing cleverness, now overruns the globe - one of the higher order of intelligence so closely akin to the animals that the gulf which separates such from them seems not very wide after all. In studying the water-crowfoots (q.v.) and other aquatic plants, we learned why submerged leaves must be so finely cut; but what mean the little bladders tipped with bristles among the pop-weed's threadlike foliage? Formerly these were regarded as mere floats - a thoughtless theory, for branches without bladders might have been observed floating perfectly. It is now known they are traps for capturing tiny aquatic creatures: nearly every bladder you examine under a microscope contains either minute crustaceans or larvae, worms, or lower organisms, some perhaps still alive, but most of them more or less advanced toward putrefaction - a stage hastened, it is thought, by a secretion within the bladders; for the plant cannot digest fresh food; it can only absorb, through certain processes within the bladder's