Of the Pyrola family (Pyrolaceae), the leaf of the small pyrola (Pyrola secunda).

Small Pyrola Leaf

Of the Pyrola family (Pyrolaceae), the leaf of the small pyrola (Pyrola secunda).

Of the Plumbago or Leadwort family (Plumbaginaceae), the marsh rosemary (Limonium carolinianum).

Marsh Rosemary

Of the Plumbago or Leadwort family (Plumbaginaceae), the marsh rosemary (Limonium carolinianum).

Of the Convolvulus family (Convolvulaceae): top, hedge bindweed (Convolvulus sepium); bottom, common dodder (Cuscuta Gronovii).

Bindweed and Dodder

Of the Convolvulus family (Convolvulaceae): top, hedge bindweed (Convolvulus sepium); bottom, common…

Of the Borage family (Boraginaceae), the Virginia stickseed (Lappula virginiana).

Virginia Stickseed

Of the Borage family (Boraginaceae), the Virginia stickseed (Lappula virginiana).

Of the Borage family (Boraginaceae), the hound's tongue (Cynoglossum officinale).

Hound's Tongue

Of the Borage family (Boraginaceae), the hound's tongue (Cynoglossum officinale).

Of the Mint family (Labiatae), the rich weed (Collinsonia Canadensis).

Rich Weed

Of the Mint family (Labiatae), the rich weed (Collinsonia Canadensis).

Of the Mint family (Labiatae), the horse mint (Mentha longifolia).

Horse Mint

Of the Mint family (Labiatae), the horse mint (Mentha longifolia).

Of the Mint family (Labiatae), the peppermint (Mentha piperita).

Peppermint

Of the Mint family (Labiatae), the peppermint (Mentha piperita).

Of the Mint family (Labiatae), the spearmint (Mentha spicata).

Spearmint

Of the Mint family (Labiatae), the spearmint (Mentha spicata).

Of the Mint family (Labiatae), the leaf of the water mint (Mentha aquatica.

Water Mint Leaf

Of the Mint family (Labiatae), the leaf of the water mint (Mentha aquatica.

Of the Mint family (Labiatae), the lower leaf of the cut-leaved water horehound (Lycopus americanus).

Cut-Leaved Water Horehound Leaf

Of the Mint family (Labiatae), the lower leaf of the cut-leaved water horehound (Lycopus americanus).

Of the Mint family (Labiatae), the leaf of the corn mint (Mentha arvensis).

Corn Mint Leaf

Of the Mint family (Labiatae), the leaf of the corn mint (Mentha arvensis).

Of the Mint family (Labiatae), the wild mint (Mentha arvensis var. Canadensis).

Wild Mint

Of the Mint family (Labiatae), the wild mint (Mentha arvensis var. Canadensis).

Of the Mint family (Labiatae), the wild bergamot (Monarda fistulosa var. rubra).

Wild Bergamot

Of the Mint family (Labiatae), the wild bergamot (Monarda fistulosa var. rubra).

Of the Mint family (Labiatae), the sage (Salvia lyrata).

Sage

Of the Mint family (Labiatae), the sage (Salvia lyrata).

Of the Mint family (Labiatae), the downy blephilia (Blephilia ciliata).

Downy Blephilia

Of the Mint family (Labiatae), the downy blephilia (Blephilia ciliata).

Of the Mint family (Labiatae), the leaf of Scutellaria nervosa.

S. nervosa Skullcap

Of the Mint family (Labiatae), the leaf of Scutellaria nervosa.

Of the Mint family (Labiatae), the leaf of the common skullcap (Scutellaria galericulata).

Common Skullcap

Of the Mint family (Labiatae), the leaf of the common skullcap (Scutellaria galericulata).

Of the Mint family (Labiatae), the leaf of Scutellaria versicolor.

S. versicolor Skullcap

Of the Mint family (Labiatae), the leaf of Scutellaria versicolor.

Of the Mint family (Labiatae), the leaf of Scutellaria parvula.

S. parvula Skullcap

Of the Mint family (Labiatae), the leaf of Scutellaria parvula.

Of the Mint family (Labiatae), the leaf of Scutellaria canescens.

S. canescens Skullcap

Of the Mint family (Labiatae), the leaf of Scutellaria canescens.

Of the Mint family (Labiatae), the leaf of Scutellaria serrata.

S. serrata Skullcap

Of the Mint family (Labiatae), the leaf of Scutellaria serrata.

Of the Mint family (Labiatae), the leaf of Scutellaria pilosa.

S. pilosa Skullcap

Of the Mint family (Labiatae), the leaf of Scutellaria pilosa.

Of the Mint family (Labiatae), the self-heal (Prunella vulgaris).

Self-Heal

Of the Mint family (Labiatae), the self-heal (Prunella vulgaris).

Of the Nightshade family (Solanaceae), the leaf and flower of the bittersweet nightshade (Solanum Dulcamara).

Bittersweet Nightshade

Of the Nightshade family (Solanaceae), the leaf and flower of the bittersweet nightshade (Solanum Dulcamara).

Of the Nightshade family (Solanaceae), the leaf and flower of the Virginia ground cherry (Physalis virginiana).

Virginia Ground Cherry

Of the Nightshade family (Solanaceae), the leaf and flower of the Virginia ground cherry (Physalis virginiana).

Of the plantain family (Plantaginaceae), the blackseed plantain (Plantago Rugelii).

Blackseed Plantain

Of the plantain family (Plantaginaceae), the blackseed plantain (Plantago Rugelii).

Of the Honeysuckle family (Caprifoliaceae), the feverwort (Triosteum perfoliatum).

Feverwort

Of the Honeysuckle family (Caprifoliaceae), the feverwort (Triosteum perfoliatum).

Of the Honeysuckle family (Caprifoliaceae), the hobble-bush (Viburnum alnifolium).

Hobble-Bush

Of the Honeysuckle family (Caprifoliaceae), the hobble-bush (Viburnum alnifolium).

Of the Valerian family (Valerianaceae), the corn salad (Valerianella Woodsiana).

Valerianella Woodsiana

Of the Valerian family (Valerianaceae), the corn salad (Valerianella Woodsiana).

Of the Gourd family (Cucurbitaceae), the leaf of the one-seeded bur-cucumber (Sicyos angulatus).

One-Seeded Bur-Cucumber

Of the Gourd family (Cucurbitaceae), the leaf of the one-seeded bur-cucumber (Sicyos angulatus).

Of the Composite family (Compositae), Joe-Pye-weed (Eupatorium purpureum)

Joe-Pye-Weed

Of the Composite family (Compositae), Joe-Pye-weed (Eupatorium purpureum)

Of the Composite family (Compositae), the leaf of the rough-stemmed golden-rod (Solidago rugosa).

Rough-Stemmed Golden-Rod

Of the Composite family (Compositae), the leaf of the rough-stemmed golden-rod (Solidago rugosa).

Of the Composite family (Compositae), the leaf of the late golden-rod (Solidago serotina).

Late Golden-Rod

Of the Composite family (Compositae), the leaf of the late golden-rod (Solidago serotina).

Of the arrowhead family (Sagittaria), the bulltongue arrowhead (Sagittaria lancifolia).

Bulltongue Arrowhead

Of the arrowhead family (Sagittaria), the bulltongue arrowhead (Sagittaria lancifolia).

Of the arrowhead family (Sagittaria), the narrow-leaved arrowhead (Sagittaria subulata).

Narrow-Leaved Arrowhead

Of the arrowhead family (Sagittaria), the narrow-leaved arrowhead (Sagittaria subulata).

Of the arrowhead family (Sagittaria), the delta arrowhead (Sagittaria platyphylla).

Delta Arrowhead

Of the arrowhead family (Sagittaria), the delta arrowhead (Sagittaria platyphylla).

Of the arrowhead family (Sagittaria), the grassy arrowhead (Sagittaria graminea).

Grassy Arrowhead

Of the arrowhead family (Sagittaria), the grassy arrowhead (Sagittaria graminea).

Of the dayflower family (Commelina), the Asiatic dayflower (Commelina communis).

Asiatic Dayflower

Of the dayflower family (Commelina), the Asiatic dayflower (Commelina communis).

The roundleaf geranium or Geranium rotundifolium.

Roundleaf Geranium

The roundleaf geranium or Geranium rotundifolium.

Of the vine family (Vitaceae), the leaf and berries of the Virginia creeper (Psedera quinquefolia).

Virginia Creeper

Of the vine family (Vitaceae), the leaf and berries of the Virginia creeper (Psedera quinquefolia).

Of the composite family (Compositae), the sharp-leaved golden-rod (Solidago arguta).

Sharp-Leaved Golden-Rod

Of the composite family (Compositae), the sharp-leaved golden-rod (Solidago arguta).

Of the composite family (Compositae), the spreading golden-rod (Solidago patula).

Spreading Golden-Rod

Of the composite family (Compositae), the spreading golden-rod (Solidago patula).

Of the composite family (Compositae), the large-leaved golden-rod (Solidago macrophylla).

Large-Leaved Golden-Rod

Of the composite family (Compositae), the large-leaved golden-rod (Solidago macrophylla).

Of the composite family (Compositae), the bog golden-rod (Solidago uliginosa).

Bog Golden-Rod

Of the composite family (Compositae), the bog golden-rod (Solidago uliginosa).

Of the composite family (Compositae), the stout golden-rod (Solidago squarrosa).

Stout Golden-Rod

Of the composite family (Compositae), the stout golden-rod (Solidago squarrosa).

Of the composite family (Compositae), the Alpine golden-rod (Solidago Cutleri).

Alpine Golden-Rod

Of the composite family (Compositae), the Alpine golden-rod (Solidago Cutleri).

Of the composite family (Compositae), the showy golden-rod (Solidago speciosa).

Showy Golden-Rod

Of the composite family (Compositae), the showy golden-rod (Solidago speciosa).

Of the composite family (Compositae), the swamp golden-rod (Solidago neglecta).

Swamp Golden-Rod

Of the composite family (Compositae), the swamp golden-rod (Solidago neglecta).

Of the composite family (Compositae), the calico aster (Aster lateriflorus).

Calico Aster

Of the composite family (Compositae), the calico aster (Aster lateriflorus).

Of the composite family (Compositae), the many-flowered aster (Aster multiflorus).

Many-Flowered Aster

Of the composite family (Compositae), the many-flowered aster (Aster multiflorus).

Of the composite family (Compositae), the small white aster (Aster vimineus).

Small White Aster

Of the composite family (Compositae), the small white aster (Aster vimineus).

Of the composite family (Compositae), the Aster tenuifolius.

Aster tenuifolius

Of the composite family (Compositae), the Aster tenuifolius.

"Fossil Fern (Neuropteris)." -Taylor, 1904

Fern Fossil

"Fossil Fern (Neuropteris)." -Taylor, 1904

"Coiling of a tendril of bryony." -Bergen, 1896

Bryony

"Coiling of a tendril of bryony." -Bergen, 1896

"Coiling of petiole of dwarf tropaeolum." -Bergen, 1896

Tropaeolum

"Coiling of petiole of dwarf tropaeolum." -Bergen, 1896

"Twining stem of hop." -Bergen, 1896

Hop

"Twining stem of hop." -Bergen, 1896

"Longitudinal section of an onion leaf. sca, thickened base of leaf, forming a bulb-scale; s, thin sheath of leaf; bl, blade of leaf; int, hollow interior of blade." -Bergen, 1896

Onion Leaf

"Longitudinal section of an onion leaf. sca, thickened base of leaf, forming a bulb-scale; s, thin sheath…

"Stem of "Smilax" (Myrsiphyllum). l, scale-like leaves; cl, cladophyll, or leaf-like branch, growing in the axil of the leaf; ped, flower-stalk, growing in the axil of a leaf." -Bergen, 1896

Smilax

"Stem of "Smilax" (Myrsiphyllum). l, scale-like leaves; cl, cladophyll, or leaf-like branch, growing…

"Tip of branch of Ailanthus in winter condition, showing very large leaf-scars and nearly naked buds." -Bergen, 1896

Ailanthus Branch

"Tip of branch of Ailanthus in winter condition, showing very large leaf-scars and nearly naked buds."…