Asplenium nidus An unbroken lance-shaped frond of the bird's-nest fern, central vein bisecting the blade.

Asplenium nidus

A bird's-nest fern lifted in March from the shaded inner court of the sister-house, its single unbroken blade rising from a rosette of pale stipes. The frond was pressed flat between cotton sheets for nine weeks before the photograph; the rachis remained green where the sunlight had not yet retreated. A specimen for the family Aspleniaceae, sheet 001 of the working register.

She named it Margaret, for the way the morning light always found it first.

Monstera deliciosa The fenestrated heart-leaf of the Swiss-cheese plant, oval lobes pierced by ovate gaps.

Monstera deliciosa

A mature blade of the Swiss-cheese plant, lifted from the sister-house conservatory after the leaf had earned its fenestration in the seventh year. The natural perforations are not damage but mature ornament, allowing wind to pass through the canopy of the rainforest. Specimen photographed in oblique morning light, family Araceae, sheet 002.

She said the holes were where the light learned to walk through the room.

Dryopteris erythrosora The autumn fern, copper-flushed when young, with a triangular bipinnate blade.

Dryopteris erythrosora

The autumn fern, a Japanese woodland species whose unfurling croziers wear a copper flush before they fade to mature evergreen. Specimen lifted from the north-facing wall of the sister-house garden, where the moss had kept the substrate damp through the dry weeks. The rachis retains the russet that gives the binomial its name. Family Dryopteridaceae, sheet 003.

She picked it on a damp October morning and called it the colour of her late father's hair.

Adiantum capillus-veneris The maidenhair fern, with its filigree of small fan-shaped pinnules on hair-thin black stipes.

Adiantum capillus-veneris

Maidenhair fern, named for the venus-fine hair of its black stipes, which carry a filigree of fan-shaped pinnules that close at dusk and at the slightest touch of water. The specimen was taken from a damp limestone fissure on the west wall, where it had naturalised over four seasons. Family Pteridaceae, sheet 004 of the working register.

She kept it on her writing-desk because she said it taught her how to be still.

Begonia rex The painted-leaf begonia with a spiralled asymmetrical blade, the lamina marked by silver concentric zones.

Begonia rex

The painted-leaf begonia, whose asymmetric heart-shaped blade carries concentric silver zones from base to apex. The specimen was raised from a wintered rhizome and lifted at first true leaf, the blade still soft enough to take the press without folding. The colouration is genetic, not pigmentary — the silver is air trapped between the upper epidermis and the palisade. Family Begoniaceae, sheet 005.

She said its silver markings looked like the moon had paused on the leaf overnight.

Ficus lyrata The fiddle-leaf fig, with a violin-shaped blade and a strong central vein.

Ficus lyrata

The fiddle-leaf fig, a West African moraceous tree whose mature leaves develop a pinched waist that gives the species its lyrate epithet. Specimen lifted from the south conservatory where it had grown to seven feet over four summers. The waxy cuticle resists the press and required ninety-three days under cotton sheets to lie flat. Family Moraceae, sheet 006 of the working register.

She turned it slowly toward each window, naming the rooms it lived through.

Hedera helix Common English ivy, a three- to five-lobed leaf with palmate venation.

Hedera helix

Common English ivy, a five-lobed mature blade taken from the north wall of the courtyard where the species had climbed the stone unaided since the year of the sister's birth. The lobes show palmate venation reduced to three primary veins in the upper leaves, a heteroblastic shift toward the reproductive form. Family Araliaceae, sheet 007 of the working register.

She measured the wall by it, said the ivy was the family's quietest clock.

Ginkgo biloba The maidenhair tree, a bilobed fan-shaped leaf with parallel dichotomous venation.

Ginkgo biloba

The maidenhair tree, a living fossil and the sole extant member of its order. The bilobed fan carries dichotomous venation in which every vein forks but never reconnects — an archaic pattern preserved unchanged for two hundred million years. Specimen taken from the corner of the sister-house lane where the autumn yellow had already begun on the upper canopy. Family Ginkgoaceae, sheet 008.

She told me the tree had been alive longer than language, and I believed her.

Pilea peperomioides The Chinese money plant, a peltate circular leaf supported by a centrally attached petiole.

Pilea peperomioides

The Chinese money plant, a peltate Pilea whose circular leaves are supported by petioles attached at the lamina's centre — an unusual architecture giving each leaf the appearance of a small green parasol. Specimen propagated from a single offset taken three years earlier from a sister herbarium in Yunnan. Family Urticaceae, sheet 009 of the working register.

She gave away every offset she could, said the plant only thrived in passing.

Calathea orbifolia The round-leaf prayer plant, a broad oval blade banded by pale concentric stripes.

Calathea orbifolia

Round-leaf prayer plant, whose broad orbicular blades fold upward each night along the central rachis and re-open at first light — the family takes its English name from this nyctinastic motion. The pale silver banding is the surface refraction of the leaf's microstructure. Family Marantaceae, sheet 010 of the working register.

She kept it by the kitchen window and called it the one who said evening prayers.

Philodendron hederaceum The heart-leaf philodendron, a cordate trailing blade with deep basal lobes.

Philodendron hederaceum

Heart-leaf philodendron, a trailing aroid whose cordate juvenile blades carry deep basal sinuses where the petiole inserts. The specimen was taken from a length that had grown over the lintel of the sister's reading-room door, a single uninterrupted vine measured at four metres on the date of pressing. Family Araceae, sheet 011 of the working register.

She trained it across the doorway because she wanted the room to greet her in green.

Tradescantia zebrina The inch plant or wandering jew, a lanceolate blade with longitudinal silver-and-violet stripes.

Tradescantia zebrina

Inch plant, a commelinaceous trailing herb whose lanceolate blades carry two longitudinal silver stripes flanking the central green panel, with a violet abaxial surface that the cotton press preserves only in flush. The species roots from a cutting in days and forms the easiest gift in the sister's catalogue. Family Commelinaceae, sheet 012 of the working register — the closing leaf.

She closed the register with it, because the easiest gifts deserve the last page.