Alg.), Alnus rotundifolia., Salix pedicellata, Prunus avium, &c.; and thus they have some elements in common with the deciduous forests of central Europe.
There were oaks, beeches (scarcely distinguishable from existing species), birches, planes and willows (one closely related to the living Salix candida), laurels, represented by Sassafras and Cinnamomum, magnolias and tulip trees (Liriodendron), myrtles, Liquidambar, Diospyros and ivy.
This was not confined to the north but may occur on the mountains of England and Wales: Salix herbacea, Silene acaulis and Dryas octopetala will serve as examples.
And Reid has shown that during the glacial period the existing flora was replaced by an arctic one represented by such plants as Salix polaris, S.
At the close of the glacial period the alpine floras retreated to the mountains accompanied by an arctic contingent, though doubtless many species of the latter, such as Salix polaris, failed to establish themselves.
The following species, none of which are found in European Russia, are characteristic of the tundras - arbutus (Arctostaphilus alpina), heaths or andomedas (Cassiope tetragona and C. hypnoides), Phyllodoce taxifolia, Loiseleuria procumbens, a species of Latifolium, a Polar azalea (Osmothamnus fragrans) and a Polar willow (Salix arctica).
Mimosa and the wild wilge-boom (Salix capensis) are the common trees on the banks and rivers, while the weeping willow is frequent round the farmsteads.
A great mass of pale-green foliage is usually composed of the algarrobo trees, while the course of the river is marked by lines or groups of palms, by fine old willows (Salix humboldtiana), fruit-gardens, and fields of cotton, Indian corn, sugar-cane and alfalfa (lucerne).
- Salix caprea - Common Sallow or Goat Willow.
2.-Salix fragilis - Crack Willow.
A narrow tract of land along the coast of the Caspian, known as the "hillocks of Baer," is covered with hillocks elongated from west to east, perpendicularly to the coast-line, the spaces between them being filled with water or overgrown with thickets of reed, Salix, Ulmus campestris, almond trees, &c. An archipelago of little islands is thus formed close to the shore by these mounds, which are backed on the N.
Thus the characteristics of the currant-gall of Spathegaster baccarum, L., which occurs alike on the leaves and on the flower-stalks of the oak, are obviously due to the act of oviposition, and not to the functions of the parts producing it; the bright red galls of the saw-fly Nematus gallicola are found on four different species of willow, Salix fragilis, S.
7 The characters of galls are constant, and as a rule exceedingly diagnostic, even when, as in the case of ten different gall-gnats of an American willow, Salix humilis, it is difficult or impossible to tell the fullgrown insects that produce them from one another.
Thus the galls of Cynips and its allies are inhabited by members of other cynipideous genera, as Synergus, Amblynotus and Synophrus; and the pine-cone-like gall of Salix strobiloides, as Walsh has shown, 2 is made by a large species of Cecidomyia, which inhabits the heart of the mass, the numerous smaller cecidomyidous larvae in its outer part being mere inquilines.
Osaria, auxaria, a bundle of osier or willow twigs), the common term under which are included the various species, varieties and hybrids of the genus Salix, used in the manufacture of baskets.
The chief species in cultivation are: Salix viminalis (the common osier) and S.
Stellaris, Erigeron alpinus, Azalea procumbens, Myosotis alpestris, Polygonum viviparum, Salix retusa, S.
These are: Festuca pulchella, Carex microstyla, Salix caesia, Rumex nivalis, Alsine aretioides, Aquilegia alpina, Thlaspi rotundifolium, Saxifraga Seguieri, S.
Salix - Willow.
With the melting of the great ice-sheet the climate became milder, and the southern part of Sweden was covered with shrubs and plants now found only in the northern and alpine parts of the country (Salix polaris, Dryas octopetala, Betula nana, &c.).
Of Phanerogams, only the Dryas octopetala covers small areas of the debris, interspersed with isolated Cochlearia, &c., and, where a layer of thinner clay has been deposited in sheltered places, the surface is covered with saxifrages, &c.; and a carpet of mosses allows the arctic willow (Salix polaris) to develop. Where a thin sheet of humus, fertilized by lemmings, has accumulated, a few flowering plants appear, but even so their brilliant flowers spring direct from the soil, concealing the developed leaflets, while their horizontally spread roots grow out of proportion; only the Salix lanata rises to 7 or 8 in., sending out roots I in.
Briancon manna is met with on the leaves of the common Larch, and bide-khecht on those of the willow, Salix fragilis; and a kind of manna was at one time obtained from the cedar.
Willows are also pretty general, the highest in growth being Salix phyllicifolia, 7 to to ft.