As to conditions of site and geographical distribution, Algae do not differ from land plants.
The concluding group of Algae is the Fucaceae, including the universally known sea wrack (Fucus).
Many Algae are beautifully coloured, even when growing at depths to which very little light penetrates.
A collection of Algaemay be fastened on sheets of paper of the usual herbarium size and kept in a cabinet or portfolios, or attached to the leaves of an album.
As in their vegetative organs, so in their reproductive, Algae exhibit many modifications of structure without much real difference.
If the coarse weeds in the rock pools and chinks are turned back, many rare and delicate Algae will be found growing under them, especially at the lowest level.
There are three points on the beach where the greatest accumulations of floating Algae are found: high water mark, mid-tide level, and low water mark.
They are little, thin, leaf-shaped creatures that creep on the bottom of ponds and even of deep lakes, or swim in the sea, and feed upon algae and minute animals.
Bacteria and blue-green algae are at the base of this.
He also began to examine Confervae, Diatoms and Desmids, finding perhaps, as others have done, that the Fresh-water Algae give the best introduction to microscopic biology.
He left Algae and Fungi (with the exception of the Characeae) alone, and it is his work on the Bryophyta and Pteridophyta that concerns us.
The fringing reef proved somewhat disappointing, for amid the multitudinous and many-coloured animal forms only a few greenAlgae were to be found.
He contributed a large proportion of the plates from his own drawings, while the descriptions throughout (excepting those of the plates on Algae and Fungi by R.
In the following year he began his Nereis Australis, or Algae of the Southern Ocean.
Part of the summer was spent in collecting Algae on the coast of Antrim; and he met again his friends Asa Gray and his wife, who were visiting Europe.
Naturally the xanthellae or yellow cells (ss 76, 90), which as independent algae live in symbiosis with many Radiolaria, must be excluded.
Very many Radiolaria, but by no means all members of this class, live in a definite commensal relation with yellow unicellular Algae of the group Xanthellae.
The disjointed Algae are generally found among the Confervae; but they are so small, and insignificant in appearance, as, in most cases, entirely to escape notice.
The jointless Algae are by far the most numerous; and they comprehend all those broad flat jelly-like substances which are called by the popular names of tangle and dulse on the coast, and which are frequently eaten.
The Algaeare divided by botanists into three classes; viz.
The jointed Algae are very inferior in the scale of creation to the first division; but the Confervae (see f in fig.
Scarcely could one still distinguish on the mauve walls the long, supple, waving, golden algae that seemed to move in obedience to the vibration of some deep and magic water.
At first it remains attached to some water weed by means of a pair of suckerlike projections; later a mouth is formed, and the tadpole begins to feed upon algae or other tiny water plants.
The Thallophytes form two groups: the Algae and the Fungi; the algaebeing green, while the fungi have no chlorophyll.
In the Green Algae (See Klebs, "Die Bedingung der Fortpflanzung.
As in the asexual reproduction of algae quantitative alteration in the amount of moisture, light, temperature, etc.
When the layer of under-ice algae forms, it absorbs light and further reduces the amount of light reaching the water (Bunt 1963).
Birds at level I feed on large algaeand seed plants and are not directly part of the same food webs involving other species.
Algae: In both the cold frame and the cold room the growth of algae is a problem.
Starting each season with completely clean sand and equipment will not prevent the appearance of algae over a long season of continuous operation.
The algae sometimes creeps up the stems of cuttings, coats the leaves, and covers terminal buds.
To date no effect is noticeable either on the algae or on the plants.
The gas is sometimes withdrawn and the deposit produced in large part by the action of algae and other humble forms of plant life.
The rock, snow-white where dry, is coated with red and orange gelatinous mats where the algae thrive in the over-flowing waters.
Gilumútan ang lubut sa tangki, The water tank is covered with algae on the bottom.
It is left in deep waters with weighted coconut fronds suspended from it, on which algae develop and attract fish which can then be caught with a net.
I uttered an exclamation of vexed disappointment when, with a splash, the head disappeared, leaving on the water a line of algae fire.
No algae or other small life was detected in the water between the ice crevices.
There, through the open panels and in a midwater of crystal clarity, our ship enabled us to study wonderful bushes of shining coral and huge chunks of rock wrapped in splendid green furs of algae and fucus.
They were huge stacks of stones in which you could distinguish the indistinct forms of palaces and temples, now arrayed in hosts of blossoming zoophytes, and over it all, not ivy but a heavy mantle of algae and fucus plants.
The trails were cluttered with algae and fucus plants, hosts of crustaceans swarming among them.
These algae are a genuine prodigy of creation, one of the wonders of world flora.
The surface of the water was crisscrossed by a floating arbor of marine plants belonging to that superabundantalgae family that numbers more than 2,000 known species.
I hear that some will cover themselves withalgae and fucus plants.
The Characeae among freshwater algae and the Sargassaceae among marine algae might be cited as examples.
He found that these places corresponded closely with the region of the absorption band for the algae under experiment.
The attachment organ of algae is thus more properly called a holdfast, and is found to be of very varied structure.
Later writers have also thought that in all four groups of algae transformations of a most far-reaching character occur.
Some are perforating algaeand burrow into the substance of molluscan shells, in company with certain Green and Blue-green Algae.
It is clear that where the bottom of a lake or sea consists of oozy mud or shifting sand, it is impossible for algae to secure a foothold.
It is perhaps desirable, in an article like this, to treat of algae in the widest possible sense in which the term may be used, an indication being at the same time given of the narrower senses in which it has been proposed to employ it.
The area included in the thick boundary line represents algae in the widest sense in which the term is used, and the four included areas the four main subdivisions.
For this purpose there will be adopted the classification ofalgae into four sub-groups, founded on the nature of the colouring matters present in the plant:-- I.
From what has been already said it is evident that among algae also strikingly similar forms exist in widely different groups.
Marine algae were present, however, so that it cannot be affirmed that the hydrocarbon of the earlier Paleozoic rocks came entirely from animal organisms.
The animal life subsisting primarily on the algaeare all invertebrates, and nearly all of them, excepting the crustaceans, simple in organization.
Below a depth of about 100 fathoms algae are absent because of lack of light, and all the deep-sea animals are believed to be carnivorous.
Seaweeds are not absent from the Arctic Ocean, although its shores, owing to the destructive action of ice, usually seem exceedingly barren, and the lower or smaller forms of algae float in the waters in abundance.
Minute simple specks of living matter, sometimes less than the five-thousandth of an inch in diameter, these lowly Algae are so numerous that it is they, in their millions, which cover moist surfaces with the familiar greenish or bluish coat.
It is, however, a true vegetable, as may be seen by dissolving away the chalky portions in acid; there is then left a vegetable framework precisely like that of other algae belonging to the same sub-class.
The Red Sea owes its colour to actual floating microscopic algae and to red coral bottoms.
There is little difficulty in getting the plants to adhere to the paper, as most of the algae are furnished with a gelatinous substance which acts like glue and fixes them firmly down.
It is only in a few sections of the lowest histona that the two kinds of sex-cells arise without a definite location in different parts of the simple tissue, as in a few groups of the lower algae and in the sponges.
The large and highly developed fucoidea among the algae exhibit similar differentiations of organs to those we distinguish as stalk and leaves in the higher cormophyta.
Other algae (such as the ulva) form thin leaf-shaped forms of the thallus, a number of homogeneous cells lying side by side along a level.
However, we must not take this division too rigidly; and the absolute lack of a nucleus and tissue-formation separates the chromacea just as widely from the multicellular tissue-forming algae as the bacteria from the fungi.
In the lower tissue-forming plants, the algae and fungi, the plant-body has the appearance of a layer of cells, the tissues of which show little or no division of labor.
In one of these appeared the imaginary derivation of the higher plants from Algae or sea-weeds.
It is found from Cape Cod to Florida among algae or rocks, and is easily recognized by its habit of rolling itself into a ball.
It grows on eel-grass and on algae below low-water mark, and is found from New York to Cape Cod.
Often the rocks at low tide are black with them; the algaethat cling in wet masses to the exposed rocks are alive with them.
The lowest forms of algae are microscopic in size, each individual being a single cell; but in the ascending scale they attain curious and beautiful shapes, some growing to a gigantic size and in forms that resemble shrubs and trees.
Algae belong to both these divisions; to the first because they have neither stems nor leaves, and to the second because they have no flowers.
Algae are nourished by the substances held in solution by the water which surrounds them.
The species forms small circular disks on algaein tide-pools.
This was in Newton Mere (Shropshire), and as this lake extends over 115 acres, it is possible to imagine the millions upon millions of algae which must have existed in it.
The names of these seaweeds are many thousand times longer than the algae themselves, and it is not really necessary to give them.
Those seaweeds were called by Horace Algae inutiles, or useless seaweeds; but are they useless?
Amongst others there is the fact that certain seaweeds or algae are found luxuriating in the hot water.
The original algae or seaweeds probably had descendants which migrated to the land and eventually after many geological periods became our flowering plants and ferns.
Even the very water is full of small, floating, vivid green stars or crescents or three-cornered pieces which are free floating Algae or Desmids.
Thus there are certain green seaweeds or algae which are said to attack and prey upon those peculiar sea-urchins known as Brittle Stars.
The starfish is carnivorous, while the sea-urchin lives on vegetable matter consisting for the most part of green algae and the red sea-weeds.
Stones with green algae on should be selected, for algae are the food of the tadpoles.
