General description:- With unisexual flowers or with all flowers bisexual or with male and female flowers on the same plant (dioecious or monoecious) herbs or shrubs, often with latex.

Leaves:- Usually alternate, simple; usually stipulate.

Flowers:- Usually actinomorphic, often without petals (apetalous) and sometimes without sepals. Male flowers with one to many stamens with free or united (connate) filaments. Female flowers with a usually 3-celled (3-locular) superior ovary and 3 styles; disc usually present, annular, with a swelling at the base (pulvinate) or cup-shaped (cyathiform); ovules 1-2 in each loculus.

Fruit:- A capsule, often dehiscing explosively; seeds often having an outgrowth or appendage at or near the hilum (carunculate).


General description:- Perennial. Monoecious. Small shrubs.

Flowers:- Solitary or in small fascicles in the leaf-axils. Sepals 5-6, free or shortly connate; petals 5-6, very small in male flowers. Male flowers with 5-6 stamens, free or connate round the rudimentary ovary; glands between the petals and stamens free or connate. Female flowers with 3-locular ovary and 3 free or shortly connate styles.

Key features:-
1) Leaves alternate, entire.


General description:- Monoecious. Annual herbs, covered with stellate hairs.

Flowers:- Male, in terminal spike-like racemes or in axillary fascicles; calyx 5-fid; petals 5; stamens 5-10, monadelphous; rudimentary ovary absent. Female flowers solitary at the base of the male; calyx 10-partite; petals absent or very small; ovary 3-locular; styles 3, 2-fid.

Key features:-
1) Inflorescence not umbellate.
2) Perianth present.
3) Flowers not surrounded by an involucre.
4) Latex absent.
5) Plant with stellate hairs.


General description:- Monoecious. Herbs or small shrubs, with latex.

Flowers:- In small groups surrounded by a more or less deeply lobed involucre with 4-5 (rarely more) glands at the top and usually pubescent within, the whole forming a cyathium. 'Inflorescence' of cyathia usually umbellate, often with axillary rays below the umbel. Perianth absent. Male flowers of a single stamen jointed to the pedicel. Female flowers solitary, with stems (pedicellate), surrounded by several male flowers; ovary 3-locular, with 3, usually free, styles; ovules solitary in each loculus.

Fruit:- Seeds usually carunculate.

In the description the inflorescence is referred to as an umbel.
The leaves subtending the primary branches (rays) of the umbel are called ray-leaves and those subtending the ultimate branches raylet-leaves.
The bracts, when present, subtend the individual male flowers in the cyathium.

Key features:-.
1) Inflorescence usually umbellate.
2) Flowers without perianth, in small groups surrounded by an involucre.
3) Latex present.

Subgen. ESULA

General description:-
Usually erect herbs or sometimes shrubs.

Leaves:- Exstipulate, usually alternate, symmetrical at base, sessile or subsessile. Cyathia almost always in umbels. Glands without petaloid appendages.

Fruit:- Seeds usually with a caruncle.


Flowers:- Glands crescentic, with short horns usually dilated and minutely lobed at the apex. Bracts between male flowers absent.


General description:- Herbs or shrubs.

Flowers:- Glands transversely ovate, not truncate, emarginate or with horns. Bracts present between the male flowers.

Fruit:- Capsule with a hardened (indurated) pericarp.


General description:- Usually procumbent annuals.

Leaves:- Stipulate, opposite, distichous, usually asymmetrical at base, petiolate.

Flowers:- Cyathia axillary or clustered, not in umbels. Glands often with petaloid appendages.

Fruit:- Seeds without a caruncle.


General description:- Annual or perennial.

Leaves:- Alternate, palmately veined.

Fruit:- Capsule with hardened (indurated) mesocarp; seeds ornamented or smooth.


General description:- Shrubs with stout branches.

Leaves:- Alternate, entire, present only on the current year's growth.

Flowers:- Glands suborbicular, entire or irregularly lobed.

Fruit:- Capsule with hardened (indurated) pericarp. Seeds smooth.


General description:- Annuals.

Leaves:- Cauline, opposite or alternate;

Fruit:- Capsule with hardened (indurated) mesocarp; seeds ornamented.


General description:- Usually dioecious. Herbs with watery sap.

Leaves:- Opposite; stipules small.

Flowers:- Male flowers usually in clusters on long axillary spikes; calyx-lobes 3; stamens 8-15. Female flowers solitary or few, axillary, almost stemless to stemmed (subsessile or pedunculate); calyx-lobes 3; styles 2.

Fruit:- With 2 cells, each with 1 seed.

Key features:-
1) Leaves opposite, entire, serrate or crenate.


General description:- Monoecious shrubs or large herbs.

Leaves:- Alternate, deeply palmately lobed.

Flowers:- Paniculate, male above, female below. Male flowers with membranous perianth; stamens numerous; filaments repeatedly branched. Female flowers with caducous, membranous perianth; ovary 3-locular.

Seeds:- 3, carunculate.