The lake is nowhere of great depth, and about midway numerous mud-banks, marshes, islands and dense growths of aqueous plants stretch across its surface.
The territories of the Gran Chaco, however, are covered with a characteristic tropical vegetation, in which the palm predominates, but intermingled south of the Bermejo with heavy growths of algarrobo, quebracho-colorado, urunday (Astronium fraxinifolium), lapacho (Tecoma curialis) and palosanto (Guayacum officinalis), all esteemed for hardness and fineness of grain.
The soil to the depth of many feet, and from it springs the most marvellous tangle of huge trees, shrubs, bushes, underwood, creepers, climbing plants and trailing vines, the whole hung with ferns, mosses, and parasitic growths, and bound together by rattans and huge rope-like trailers.
It is usual for the umbrella to have an even, circular, uninterrupted margin; but in the order Narcomedusae secondary down-growths between the tentacles produce a lobed, indented margin to the umbrella.
P. alba suffers much from the ravages of wood-eating larvae, and also from fungoid growths, especially where the branches have been removed by pruning or accident.
Aphidesand may be easily penetrated by certain Fungi such as Peziza, Nectria; and when thus attacked, the repeated conflicts between the cambium and callus, on the one hand, trying to heal over the wound, and the insect or Fungus, on the other, destroying the new tissues as they are formed, results in irregular growths; the still uninjured cambium area goes on thickening the branch, the dead parts, of course, remain unthickened, and the portion in which the Fungus is at work may for the time being grow more rapidly.
Mould and bacterial growths, and causing the appearance, on the surface of their " mushroom garden," of numerous small white bodies formed by swollen ends of the fungus hyphae.
A, Winged female; B, winged D, viviparous wingless female from in patches from old apple trees, where the insects live in the rough bark and form cankered growths both above and below ground.
Upon the surface of the visceral dome, and extending special pallial growths, comparable with those of Pleurophyllidia).
Others have hollow or funnel-shaped ends and are constricted at the middle like a dice cup. In some rocks small rod-like microlites are grouped together in a regular way to form growths which resemble fir branches, fern leaves, brushes or networks, in the same manner as minute needles of ice produce star-like snow crystals or the frost growths on a window pane.
In the case of a tree from seven to ten years old, tapping is so arranged that by the time the last incisions on the original growth are made, the new growths on other portions are at least four years old, and ready for new incisions to be made.
The application of an infusion of violet leaves was at one time believed to have the power of reducing the size of cancerous growths, but its use is now discredited.
Tumours Or New Growths The various definitions of the term " new growth " leave us with a definite conception of it as a new formation of tissue which appears to originate and to grow independently.
All the hypotheses about the causation of new growths seek to explain the secret of this individuality or " autonomy," as they recognize that the mystery of the origin of the great majority of tumours would be solved if we could trace how or why the tissue elements in which they develop first took on this abnormal growth.
In spite of all the valuable research work that has been done within the last few years, the essential cause of new growths still remains unknown.
Their investigations on cancers found in the lower animals, and the successful transplantation of such growths into a new host of the same species (mice and rats), have greatly advanced our knowledge of the etiology of this disease.
He holds that new growths arise, both before birth or at any subsequent period of life, by the separation of cells or clumps of cells from their normal position, and that in health there is a balance between the various tissues and tissue elements regulated by what he calls the " tissue-tension " of the part, i.e.
Hansemann's "anaplasia " hypothesis seeks to find an explanation of the formation of new growths in the absence of the histological differentiation of the cell associated with a corresponding increase in its proliferative power and a suspension, or loss, of its functional activity.
In recent years the successful experimental transplantation of new growths, occurring sporadically in white mice and rats, into animals of the same species, has thrown a fresh light on all the features of malignant growths.
From these experiments it is shown that cells taken from these growths and introduced into animals of the same species give rise to a cancerous growth, whose cells have acquired unlimited powers of proliferation.
The foregoing hypotheses have all sought the origin of new growths in some intrinsic cause which has altered the characters of the cell or cells which gave rise to them, but none of them explain the direct exciting cause.
Many cancer-parasites have been described in cancerous growths, including bacteria, yeasts and protozoa, but the innumerable attempts made to demonstrate the causal infective organism have all completely failed.
At the present time we are quite uncertain what is the ultimate cause of new growths; in all probability there may be one or more aetiological factors at play disturbing that perfect condition of equilibrium of normal tissues.
These changes are found in senile wasting, in metaplasia of cartilage, in many tumours, especially mixed growths of the parotid gland and testicle, and in various inflammatory granulation ulcers.
The trees form their heads naturally, and therefore little pruning is required, it being merely necessary to cut off straggling growths, and to prevent the branches from interlacing.
The zoarium may rise up into erect growths composed of a single layer of zooids, the orifices of which are all on one surface, or of two layers of zooids placed back to back, with the orifices on both sides of the fronds or plates.
Of which, covering a large part of the state, are magnificent forests of long-leaf pine, and lesser lowland growths of oak, ash, magnolia, cypress and other valuable timber.
The Nepidae breathe by means of a pair of long, grooved tail processes (really out-growths c, labrum; d, epipharynx.
The pine and hardwood areas occur chiefly in the north-eastern part of the state, and are bordered on the west by scattering growths of hardwood, extending as far westward as Austin.
Outside of these general areas, forest products are of relatively little value, the exceptions being the dense growths, in certain restricted areas, of live-oak, which is in demand for ship timbers; and scattering patches of hickory, which is requisite for certain manufactures.
West of the dividing crest they are forest clad; east thereof their stony grimness is but slightly softened by growths of scrub and tussock grass.
Considering, however, that it is generally believed that Bryophyta and vascular plants are descended from an algal ancestry, it is natural to suppose that, prior to the luxuriant vegetable growths of the Carboniferous period, there must have existed an age of algae.
There has been constant controversy as to whether China tea is better than that of other growths, but the verdict first of all of Great Britain, and subsequently of all the other large consuming countries, has relegated the produce of the Celestial Empire to a very subordinate position.
In Ceylon, and to some extent in India, the careful and systematic application of chemical manures, compounded on scientific lines, has been found to increase largely the yield of leaf, and much interplanting of nitrogen-producing growths has been done with a view to restoring to the soil the most necessary constituents.
- Diagram showing the alterations in the relative proportions of different growths of tea consumed during the 21 years ended the 31st of December 1907; the variations in the London average prices for Indian teas, and the changes in the English rate of duty.
After flowering the plant dies down, but increases by new lateral growths from the rootstock.
The conditions under which the beds of coal were formed will be found described under that head; it will be sufficient to notice here that some coal seams were undoubtedl y formed by jungle or swamplike growths on the site of the deposit, and it is equally true that others were formed by the transport and deposition of vegetable detritus.
It is also important to select leafy growths, and not such as will at'once run up to flower.
In forming a pyramidal tree, the lateral growths, instead of being removed, as in the standard tree, are encouraged to the utmost; and in order to strengthen them the upper part of the leading shoot is removed annually, the side branches being also shortened somewhat as the tree advances in size.
Sometimes in very favourable soils and with vigorous trees two pairs of branches may be obtained in one season by summerstopping the erect shoots and selecting others from the young growths thus induced, but more commonly the trees have to be built up by forming one pair of branches annually.
The gardener aims usually at producing stout, robust, short-jointed stems, instead of long lanky growths defective in woody tissue.
The edges of the leaves of Bryophyllum calycinum and of Cardamine pratensis, and the growths in the axils of the leaves of Lilium bulbiferum, as well as the fronds of certain ferns (e.g.