This ClipArt gallery offers 113 images of algae. Algae are eukaryotic organisms that lack many organs found in land plants. The most known and largest examples are seaweeds.

"An order of the class Infusoria, the adult members of which have no cilia and no proper mouth, and are non-locomotive." -Whitney, 1902

Acinetæ

"An order of the class Infusoria, the adult members of which have no cilia and no proper mouth, and…

Magnified view of some of a simple fresh water Alga, the Tetraspora lubrica, each sphere of which may answer to an individual plant.

Alga

Magnified view of some of a simple fresh water Alga, the Tetraspora lubrica, each sphere of which may…

"A division of thallogenous chlorophyllous cryptograms found in the most part in the sea or in freshwater."-Whitney, 1902

Algae

"A division of thallogenous chlorophyllous cryptograms found in the most part in the sea or in freshwater."-Whitney,…

"a genus of algae. P.nivalis (red-snow) appears on the surface of snow, tinging extensive tracts in the Arctic regions or amongst the Alps, in an incredibly short space of time, with a deep crimson. This plant may be regarded a s one of the simplest forms of vegetation." -Marshall

Protococcus Algae

"a genus of algae. P.nivalis (red-snow) appears on the surface of snow, tinging extensive tracts in…

An animal that lives in stagnant water. It is so small that it can only be seen with a microscope.

Amebas

An animal that lives in stagnant water. It is so small that it can only be seen with a microscope.

"Piece of the frond of Fucus platycarpus furnished with receptacles." -Lindley, 1853

Brown Alga

"Piece of the frond of Fucus platycarpus furnished with receptacles." -Lindley, 1853

"Fucus platycarpus...Section of a conceptacle much magnified." -Lindley, 1853

Brown Alga

"Fucus platycarpus...Section of a conceptacle much magnified." -Lindley, 1853

"Fucus platycarpus...3. jointed branching hairs detached from the sides of the conceptacle and bearing antherids; 4. an antherid full; 5. an antherid with only one antherozoid left in it; 6. Antherozoids." -Lindley, 1853

Brown Alga

"Fucus platycarpus...3. jointed branching hairs detached from the sides of the conceptacle and bearing…

Bryopsis plumosa; apex of a stem with its branchlets; all the extension of one cell.

Bryopsis Plumosa

Bryopsis plumosa; apex of a stem with its branchlets; all the extension of one cell.

Plant body made up of stems bearing whorled, brittle branches.

Chara

Plant body made up of stems bearing whorled, brittle branches.

They grow in pools and slow streams rooting in the ground and growing erect. Some species when taken out of the water emit a very disagreeable odor, like that of a sulphuric hydrogen. They occur all over the world, but mostly in temperate climates.

Chara

They grow in pools and slow streams rooting in the ground and growing erect. Some species when taken…

Branch of a Chara

Chara

Branch of a Chara

Outlines of a portion of the stem in section, showing the central cell and the outer or cortical cells.

Chara

Outlines of a portion of the stem in section, showing the central cell and the outer or cortical cells.

"1. Antherid and spore-case of Chara fragilis not much magnified; 2. the same at a later period, after the dehiscence of the antherid; 3. three of the valves which cover the antherid represented at the moment of dehiscence; 4. an empty tube, in which a few antherozoids are left; 5. Anteroizoids." -Lindley, 1853

Chara fragilis

"1. Antherid and spore-case of Chara fragilis not much magnified; 2. the same at a later period, after…

Chara vulgaris, a modern lime-secreting alga, growing in fresh water. An important marl and limestone former.

Chara Vulgaris

Chara vulgaris, a modern lime-secreting alga, growing in fresh water. An important marl and limestone…

Chara vulgaris, a recent calcareous alga (fresh water); sport-vessel with corona. This is frequently found in great numbers in fresh-water limestones, showing their mode of origin.

Chara Vulgaris

Chara vulgaris, a recent calcareous alga (fresh water); sport-vessel with corona. This is frequently…

This illustration shows the features in the life history of Chlamydomonas: A, character of the motile plant. B, conjugation of isogamous gametes. C, a plant dividing to form numerous small male gametes. D, a plant forming two large female gametes. E, male and female gametes about to conjugate.

Chlamydomonas

This illustration shows the features in the life history of Chlamydomonas: A, character of the motile…

"D, cell of Oedogonium, with numerous chloroplasts." -Stevens, 1916

Oedogonium Chloroplast

"D, cell of Oedogonium, with numerous chloroplasts." -Stevens, 1916

"A, Pleurococcus, with chloroplast at c." -Stevens, 1916

Pleurococcus Chloroplast

"A, Pleurococcus, with chloroplast at c." -Stevens, 1916

"B, cell of Spirogyra, with spiral chloroplast at c, nucleus at n, and pyrenoid at e." -Stevens, 1916

Spirogyra Chloroplast

"B, cell of Spirogyra, with spiral chloroplast at c, nucleus at n, and pyrenoid at e." -Stevens, 1916

"C, cross section of Spirogyra cell, with nucleus at n, and section of chloroplast and pyrenoid below." -Stevens, 1916

Spirogyra Chloroplast

"C, cross section of Spirogyra cell, with nucleus at n, and section of chloroplast and pyrenoid below."…

Small plant of Chondrus crispus, Carrageen Moss; the spots represent the fructification, consisting of numerous tetraspores in bunches in the substance of the plant.

Chondrus Crispus

Small plant of Chondrus crispus, Carrageen Moss; the spots represent the fructification, consisting…

Two of the tetraspores from the Chondrus crispus.

Chondrus Crispus Tetraspores

Two of the tetraspores from the Chondrus crispus.

The growing end of a branching Conferva (Cladophora glomerata), showing how, by a kind of budding growth, a new cell is formed by a cross partition separating the newer tip from the older part below; also, how the branches arise.

Conferva

The growing end of a branching Conferva (Cladophora glomerata), showing how, by a kind of budding growth,…

Corallina, a modern lime-secreting alga (entire plant).

Corallina

Corallina, a modern lime-secreting alga (entire plant).

Corallina, a modern lime-secreting alga (a small branch enlarged).

Corallina

Corallina, a modern lime-secreting alga (a small branch enlarged).

Coralline Rock is a type of rock formed by the death of layers of Coralline algae. It is visually quite bright like the algae, and is often desired as aquarium decoration. Since it is formed from the dead algae, it contains some nutrients and calcium carbonate, which has allowed it to be used in some building structures.

Coralline

Coralline Rock is a type of rock formed by the death of layers of Coralline algae. It is visually quite…

A piece of the rose-red Delesseria Lepreiurei

Delesseria Lepreiurei

A piece of the rose-red Delesseria Lepreiurei

A piece of the rose-red Delesseria Lepreiurei, showing that it is composed of a layer of cells.

Delesseria Lepreiurei

A piece of the rose-red Delesseria Lepreiurei, showing that it is composed of a layer of cells.

A piece of the rose-red Delesseria Lepreiurei, showing the cells are gelatinous and thick-walled.

Delesseria Lepreiurei

A piece of the rose-red Delesseria Lepreiurei, showing the cells are gelatinous and thick-walled.

Section through a conceptacle of Delesseria Leprieurei, showing the spores, which are single specialized cells, two or three in a row.

Delesseria Lepriuerei

Section through a conceptacle of Delesseria Leprieurei, showing the spores, which are single specialized…

Closterium acutum, a common Desmid. It is a single firm-walled cell, filled with green protoplasmic matter.

Desmid

Closterium acutum, a common Desmid. It is a single firm-walled cell, filled with green protoplasmic…

View of three stages of the conjugation

Desmid

View of three stages of the conjugation

Diatoms are a major group of eukaryotic algae. The individuals are joined in a zigzag band.

Diatoms

Diatoms are a major group of eukaryotic algae. The individuals are joined in a zigzag band.

These protozoans form colonies. A mature spherical colony of Eudorina.

Eudorina

These protozoans form colonies. A mature spherical colony of Eudorina.

These protozoans form colonies. Formation of the two kinds of reproductive cells of Eudorina.

Eudorina

These protozoans form colonies. Formation of the two kinds of reproductive cells of Eudorina.

"Eudorina. The development of reproductive bodies within the colony from the ordinary vegetative cells (v). f, a mass of female cells; m, a mass of male or motile cells; f', a single female cell surrounded by male cells (m'); q, the boundary of the original colony." -Galloway, 1915

Eudorina

"Eudorina. The development of reproductive bodies within the colony from the ordinary vegetative cells…

Magnified section through a fertile conceptacle of Rockweed, showing the large spores in the midst of threads of cells.

Fertile Conceptacle of Rockweed

Magnified section through a fertile conceptacle of Rockweed, showing the large spores in the midst of…

Flagellata is an order of Protozoa characterized by the presence of flagellae (whip-like structures used for locomotion). In many flagellate forms, chlorophyll is present. These forms have been regarded by botanists as minute algae. This illustration shows 3 flagellates: 1) Ceratium Tripos, 2) Noctiluca, and 3) Euglena.

Flagellata

Flagellata is an order of Protozoa characterized by the presence of flagellae (whip-like structures…

Foraminifera are minute shelled animalcules. They secrete a hard covering or shell made of sand or carbonate of lime. This lagena has a single-chambered shell.

Foraminifera

Foraminifera are minute shelled animalcules. They secrete a hard covering or shell made of sand or carbonate…

Foraminifera are minute shelled animalcules. They secrete a hard covering or shell made of sand or carbonate of lime. This Miliola shows a thread-like pseudopodia protruded from the mouth of the shell.

Foraminifera

Foraminifera are minute shelled animalcules. They secrete a hard covering or shell made of sand or carbonate…

Foraminifera are minute shelled animalcules. They secrete a hard covering or shell made of sand or carbonate of lime. This Discorbina shows the many-chambered shell with the psdeudopodia protruded from the entire surface of the shell by minute apertures.

Foraminifera

Foraminifera are minute shelled animalcules. They secrete a hard covering or shell made of sand or carbonate…

Foraminifera are minute shelled animalcules. They secrete a hard covering or shell made of sand or carbonate of lime. This section of Nodosaria shows the chambers.

Foraminifera

Foraminifera are minute shelled animalcules. They secrete a hard covering or shell made of sand or carbonate…

Foraminifera are minute shelled animalcules. They secrete a hard covering or shell made of sand or carbonate of lime. This is Nodosaria hispida.

Foraminifera

Foraminifera are minute shelled animalcules. They secrete a hard covering or shell made of sand or carbonate…

The Foraminifera, ("Hole Bearers") or forams for short, are a large group of amoeboid protists with reticulating pseudopods, fine strands of cytoplasm that branch and merge to form a dynamic net. They typically produce a test, or shell, which can have either one or multiple chambers, some becoming quite elaborate in structure. These shells are made of calcium carbonate (CaCO3) or agglutinated sediment particles. About 275,000 species are recognized, both living and fossil. They are usually less than 1 mm in size, but some are much larger, and the largest recorded specimen reached 19 cm.

Foraminifera

The Foraminifera, ("Hole Bearers") or forams for short, are a large group of amoeboid protists…

"Fucus vesiculosus: showing the receptacles of the fructification a, a, at the ends of the branching frond; b, b, b, large air-cells which help to float the plant." — Chambers' Encyclopedia, 1875

Fucus Vesiculosus

"Fucus vesiculosus: showing the receptacles of the fructification a, a, at the ends of the branching…

Globigerina, a type of foraminiferan, has a kind of chalk-like shell.

Globigerina

Globigerina, a type of foraminiferan, has a kind of chalk-like shell.

These protozoans form colonies. Gonium pectorale colony seen from above.

Gonium

These protozoans form colonies. Gonium pectorale colony seen from above.

These protozoans form colonies. Gonium pectorale colony seen from the side.

Gonium

These protozoans form colonies. Gonium pectorale colony seen from the side.

This illustration shows the colonial forms of unicellular green algae: A, Pediastrum, the plants of the colony being arranged in a flat plate. B, a view of the outer cells of the colony showing the formation of a new colony. C, one of these new colonies. D, a plant of the water net containing a young colony. E, enlarged view of one of the meshes of a net showing the geometrical arrangement of the plants.

Green Algae

This illustration shows the colonial forms of unicellular green algae: A, Pediastrum, the plants of…

Gregarina is a parasitic protozoan. They live in the alimentary canal of crayfish, and certain insects.

Gregarina

Gregarina is a parasitic protozoan. They live in the alimentary canal of crayfish, and certain insects.

Gregarina is a parasitic protozoan. Stage 2 in the conjugation and spore forming.

Gregarina

Gregarina is a parasitic protozoan. Stage 2 in the conjugation and spore forming.

Gregarina is a parasitic protozoan. Stage 3 in the conjugation and spore forming.

Gregarina

Gregarina is a parasitic protozoan. Stage 3 in the conjugation and spore forming.

"Branch of Gulfweed (Sargassum bacciferum). a, vesicle with leaf; b, mucronate vesicle." -Whitney, 1911

Gulfweed Branch

"Branch of Gulfweed (Sargassum bacciferum). a, vesicle with leaf; b, mucronate vesicle." -Whitney, 1911

Halimeda tuna, a lime-secreting green alga from the modern sea; attached to rocks.

Halimeda Tuna

Halimeda tuna, a lime-secreting green alga from the modern sea; attached to rocks.

An illustration of a heterostegina, a prehistoric foraminifera.

Heterostegina

An illustration of a heterostegina, a prehistoric foraminifera.

Oarweed or Tangle (Laminaria digitata) is a species of kelp common to the British Isles and Northeast America.

Oarweed

Oarweed or Tangle (Laminaria digitata) is a species of kelp common to the British Isles and Northeast…

Oarweed or Kelp (Laminaria longicruris) is a species of kelp common to Northeast America.

Oarweed

Oarweed or Kelp (Laminaria longicruris) is a species of kelp common to Northeast America.

Similar section of a sterile conceptacle, containing slender antheridia.

Marine Algae of New England

Similar section of a sterile conceptacle, containing slender antheridia.

An illustration of the Noctiluca scintillans. Noctiluca scintillans, also published as Noctiluca miliaris, is a free-living non-parasitic marine-dwelling species of dinoflagellate that exhibits bioluminescence. The bioluminescent characteristic of N. scintillans is produced by a luciferin-luciferase system located in thousands of spherically shaped organelles, or "microsources", located throughout the cytoplasm of this single-celled protist. Nonluminescent populations within the genus Noctiluca lack these microsources.

Noctiluca Scintillans

An illustration of the Noctiluca scintillans. Noctiluca scintillans, also published as Noctiluca miliaris,…