This shows a sprouting acorn (Keeler, 1915).

Acorn

This shows a sprouting acorn (Keeler, 1915).

Nut (acorn) of the Oak, with its cup or cupule.

Acorn

Nut (acorn) of the Oak, with its cup or cupule.

This shows the acorn of Bear Oak, Quercus ilicifolia, (Keeler, 1915).

Bear Oak Acorn

This shows the acorn of Bear Oak, Quercus ilicifolia, (Keeler, 1915).

This shows the acorn of Black Jack Oak, Quercus marilandica, (Keeler, 1915).

Black Jack Oak Acorn

This shows the acorn of Black Jack Oak, Quercus marilandica, (Keeler, 1915).

This shows the acorn of Black Oak, Quercus velutina, (Keeler, 1915).

Black Oak Acorn

This shows the acorn of Black Oak, Quercus velutina, (Keeler, 1915).

This shows the acorn of Bur Oak, Quercus macrocarpa, (Keeler, 1915).

Bur Oak Acorn

This shows the acorn of Bur Oak, Quercus macrocarpa, (Keeler, 1915).

This shows the acorn of chestnut Oak, Quercus prinus, (Keeler, 1915).

Chestnut Oak Acorn

This shows the acorn of chestnut Oak, Quercus prinus, (Keeler, 1915).

This shows the acorn of Chinquapin Oak, Quercus prinoides, (Keeler, 1915).

Chinquapin Oak Acorn

This shows the acorn of Chinquapin Oak, Quercus prinoides, (Keeler, 1915).

This shows the acorn of Pin Oak, Quercus palustris, (Keeler, 1915).

Pin Oak Acorn

This shows the acorn of Pin Oak, Quercus palustris, (Keeler, 1915).

This shows the acorn of Post Oak, Quercus minor, (Keeler, 1915).

Post Oak Acorn

This shows the acorn of Post Oak, Quercus minor, (Keeler, 1915).

This shows the acorn of Red Oak, Quercus rubra, (Keeler, 1915).

Red Oak Acorn

This shows the acorn of Red Oak, Quercus rubra, (Keeler, 1915).

This shows the acorn of Scarlet Oak, Quercus coccinea, (Keeler, 1915).

Scarlet Oak Acorn

This shows the acorn of Scarlet Oak, Quercus coccinea, (Keeler, 1915).

This shows the acorn of Shingle Oak, Quercus imbricaria, (Keeler, 1915).

Shingle Oak Acorn

This shows the acorn of Shingle Oak, Quercus imbricaria, (Keeler, 1915).

This shows acorns of Spanish Oak, Quercus digitata, (Keeler, 1915).

Spanish Oak Acorn

This shows acorns of Spanish Oak, Quercus digitata, (Keeler, 1915).

This shows the acorn of Swamp White Oak, Quercus platanoides, (Keeler, 1915).

Swamp Oak Acorn

This shows the acorn of Swamp White Oak, Quercus platanoides, (Keeler, 1915).

This shows the acorn of Willow Oak, Quercus phellos, (Keeler, 1915).

Willow Oak Acorn

This shows the acorn of Willow Oak, Quercus phellos, (Keeler, 1915).

This shows the acorn of Yellow Oak, Quercus acuminata, (Keeler, 1915).

Yellow Oak Acorn

This shows the acorn of Yellow Oak, Quercus acuminata, (Keeler, 1915).

Adder-Tongue, Ophioglossum: spore-cases in a kind of spike: <em>a</em>, a portion of the fruiting part , above natural size; showing two rows of the firm spore-cases, which open transversely into two selves.

Adder-Tongue

Adder-Tongue, Ophioglossum: spore-cases in a kind of spike: a, a portion of the fruiting part…

The almond is native to Iran, from northwestern Saudi Arabia, north through western Jordan, Israel, Lebanon, western Syria, to southern Turkey. It is a small deciduous tree, growing to between 4 and 10 meters in height, with a trunk of up to 30 centimeters in diameter. The young shoots are green at first, becoming purplish where exposed to sunlight, then grey in their second year. The leaves are 1 cm long and 1.2&ndash;4 cm broad, with a serrated margin and a 2.5 cm petiole. The flowers are white or pale pink, 3&ndash;5 cm diameter with five petals, produced singly or in pairs before the leaves in early spring. The fruit is a drupe 3.5&ndash;6 cm long, with a downy outer coat. The outer covering or exocarp, (fleshy in other members of Prunus such as the plum and cherry), is instead a leathery grey-green coating called the hull, which contains inside a hard shell, and the edible seed, commonly called a nut in culinary terms. Generally, one seed is present, but occasionally there are two. In botanical terms, an almond is not a true nut. The reticulated hard woody shell (like the outside of a peach pit) surrounding the edible seed is called the endocarp. The fruit is mature in the autumn, 7&ndash;8 months after flowering.

Almond Tree and Fruit

The almond is native to Iran, from northwestern Saudi Arabia, north through western Jordan, Israel,…

This shows the leaf of the Almondleaf Willow, Salix amygdaloides, (Keeler, 1915).

Almondleaf Willow Leaf

This shows the leaf of the Almondleaf Willow, Salix amygdaloides, (Keeler, 1915).

Utricle (pyxis) of Amaranth, opening all around (circumscissile).

Amaranth

Utricle (pyxis) of Amaranth, opening all around (circumscissile).

Flower of Anemone Pennsylvanica; apetalous, hermaphrodite

Anemone Pennsylvanica

Flower of Anemone Pennsylvanica; apetalous, hermaphrodite

"Anona furfuracea. 1. an expanded flower; 2. a vertical section of male and female apparatus, which latter occupies the centre; 3. a vertical section of a carpel; 4. ditto of a ripe seed, showing the ruminated albumen and embryo." -Lindley, 1853

Annona

"Anona furfuracea. 1. an expanded flower; 2. a vertical section of male and female apparatus, which…

Diagram of the lower part of an anther, cut across above, and the upper part of a leaf, to show how the one answers to the other; the filament to petiole, the connective to midrib; the two cells to the right and left halves of the blade.

Anther

Diagram of the lower part of an anther, cut across above, and the upper part of a leaf, to show how…

Section of a smaller apothecium.

Apothecium

Section of a smaller apothecium.

"Perpendicular section of the fruit of Pyrus malus." -Lindley, 1853

Apple

"Perpendicular section of the fruit of Pyrus malus." -Lindley, 1853

"Aptandra Spruceana. 1. an expanded flower; 2. a petal; 3. tube of stamens, with 4 petaloid glands at the base; 4. pistil; 5. section of ovary." -Lindley, 1853

Aptandra

"Aptandra Spruceana. 1. an expanded flower; 2. a petal; 3. tube of stamens, with 4 petaloid glands at…

Branch of Arbor-Vitae, with awl-shaped and scale-shaped leaves.

Arbor-Vitae

Branch of Arbor-Vitae, with awl-shaped and scale-shaped leaves.

Branchlet of the American Arbor-Vitae, considerably larger than in nature, terminated by its pistillate flowers, each consisting of a single scale (an open pistil), together forming a small cone.

Arbor-Vitae

Branchlet of the American Arbor-Vitae, considerably larger than in nature, terminated by its pistillate…

One of the scales or carpels of the American Arbor-Vitae, the inside exposed to view, showing a pair of ovules on its base.

Arbor-Vitae

One of the scales or carpels of the American Arbor-Vitae, the inside exposed to view, showing a pair…

Arum maculatum: "A single fruit divided vertically, so as to show the seeds in situ. A perpendicular section of one of the seeds." -Lindley, 1853

Wild Arum Fruit and Seed

Arum maculatum: "A single fruit divided vertically, so as to show the seeds in situ. A perpendicular…

"Athamanta cervariaefolia. 1. a separate flower, with hairy petals; 2. a petal by itself; 3. a ripe fruit with the two carpels or mericarps separating from the double carpopod or axis; 4. a seed deprived of its integuments, and divided vertically, so as to show the position of the embryo." -Lindley, 1853

Athamantha

"Athamanta cervariaefolia. 1. a separate flower, with hairy petals; 2. a petal by itself; 3. a ripe…

"Lophira alata. a an anther; b a perpendicular section of an ovary; e a fruit; d a perpendicular section of a fruit." -Lindley, 1853

Azobe

"Lophira alata. a an anther; b a perpendicular section of an ovary; e a fruit; d a perpendicular section…

Small plant of Azolla Caroliniana.

Azolla Caroliniana

Small plant of Azolla Caroliniana.

Small plant of Azolla Caroliniana, showing two kinds of sporocarp; the small ones contain microspores.

Azolla Caroliniana

Small plant of Azolla Caroliniana, showing two kinds of sporocarp; the small ones contain microspores.

Small plant of Azolla Caroliniana, showing a sporocarp; the small ones contain microspores.

Azolla Caroliniana

Small plant of Azolla Caroliniana, showing a sporocarp; the small ones contain microspores.

A larger sporocarp of the Azolla Caroliniana, more magnified.

Azolla Caroliniana

A larger sporocarp of the Azolla Caroliniana, more magnified.

A larger sporocarp of the Azolla Caroliniana, more magnified and burst open, showing stalked spore-cases.

Azolla Caroliniana

A larger sporocarp of the Azolla Caroliniana, more magnified and burst open, showing stalked spore-cases.

Two sporoscopes of the Azolla Caroliniana; one of them bursting shows four contained macrospores between the two, three of these spores highly magnified.

Azolla Caroliniana

Two sporoscopes of the Azolla Caroliniana; one of them bursting shows four contained macrospores between…

This shows the staminate flower of the Balsam, Populus balsamifera, (Keeler, 1915).

Balsam Flower

This shows the staminate flower of the Balsam, Populus balsamifera, (Keeler, 1915).

This shows the pistillate flower of the Balsam, Populus balsamifera, (Keeler, 1915).

Balsam Flower

This shows the pistillate flower of the Balsam, Populus balsamifera, (Keeler, 1915).

This shows the fruiting aments of the Balsam, Populus balsamifera, (Keeler, 1915).

Balsam Fruit

This shows the fruiting aments of the Balsam, Populus balsamifera, (Keeler, 1915).

"Impatiens macrochila; 2. a diagram of its flower; 3. its stamens; 4. fruit of I. Balsamina (rose balsam); 5. its embryo." -Lindley, 1853

Large-Lipped Balsam

"Impatiens macrochila; 2. a diagram of its flower; 3. its stamens; 4. fruit of I. Balsamina (rose balsam);…

Magnified wood-cells of the bark (bast-cells) of Basswood, one and part of another.

Basswood

Magnified wood-cells of the bark (bast-cells) of Basswood, one and part of another.

Magnified wood-cells of the bark (bast-cells) of Basswood, one and part of another.

Basswood

Magnified wood-cells of the bark (bast-cells) of Basswood, one and part of another.

This shows the staminate flower of the Beech, (Keeler, 1915).

Beech Flower

This shows the staminate flower of the Beech, (Keeler, 1915).

This shows the pistillate flower of the Beech, (Keeler, 1915).

Beech Flower

This shows the pistillate flower of the Beech, (Keeler, 1915).

This shows the staminate and pistillate flower cluster of the Beech, (Keeler, 1915).

Beech Flower

This shows the staminate and pistillate flower cluster of the Beech, (Keeler, 1915).

"The berry is a succulent, syncarpous fruit, in which the seeds are immersed in a pulpy mass, formed by the placentas."&mdash;Darby, 1855

Berry

"The berry is a succulent, syncarpous fruit, in which the seeds are immersed in a pulpy mass, formed…

Catkin or ament of birch.

Birch

Catkin or ament of birch.

Seed of Bitter Cress, Barbarea, cut across to show the accumbent cotyledons.

Bitter Cress

Seed of Bitter Cress, Barbarea, cut across to show the accumbent cotyledons.

Whole embryo of Bitter Cress, Barbarea.

Bitter Cress

Whole embryo of Bitter Cress, Barbarea.

This is the fruit of Bitternut, Hicoria minima, (Keeler, 1915).

Bitternut Fruit

This is the fruit of Bitternut, Hicoria minima, (Keeler, 1915).

This is the staminate flower of Black Ash, Fraxinus nigra, (Keeler, 1915).

Black Ash Flower

This is the staminate flower of Black Ash, Fraxinus nigra, (Keeler, 1915).

This is the pistillate flower of Black Ash, Fraxinus nigra, (Keeler, 1915).

Black Ash Flower

This is the pistillate flower of Black Ash, Fraxinus nigra, (Keeler, 1915).

This is the fruit, or samara, of Black Ash, Fraxinus nigra, (Keeler, 1915).

Black Ash Fruit

This is the fruit, or samara, of Black Ash, Fraxinus nigra, (Keeler, 1915).

This shows the staminate flower of the Black Willow, Salix nigra, (Keeler, 1915).

Black Willow Flower

This shows the staminate flower of the Black Willow, Salix nigra, (Keeler, 1915).

This shows the pistillate flower of the Black Willow, Salix nigra, (Keeler, 1915).

Black Willow Flower

This shows the pistillate flower of the Black Willow, Salix nigra, (Keeler, 1915).

Section of a part of a blackberry.

Blackberry

Section of a part of a blackberry.

One of its component simple fruits (drupe) in section, showing the pulp, stone, and contained seed.

Blackberry

One of its component simple fruits (drupe) in section, showing the pulp, stone, and contained seed.