Order 3. PORTULACALES 
Portulacales nobis; Portulacineae Engler Syll. ed. 2, 1 1 3 (1898); Carter Gen. Brit. Plants 42 (1913). 
Leaves stipulate or not, alternate or opposite. Flowers bracteate or ebracteate. Perianth 
heterochlamydeous. Calyx consisting of 2 (rarely 4 — 8), median, nearly opposite sepals 1 . Corolla 
with 3 — 6, usually 5 petals, polypetalous or gamopetalous. Stamens 1 — 00 ; if 5, antipetalous. 
Carpels 2 — 8. Fruit a pyxidium, or capsule, or berry. Placentation basal. Endosperm present. 
See also Volume II, page 150. Only British family: — Portulacaceae. 
Family 1. PORTULACACEAE 
Portulacaceae Lindley Nat. Arr. ed. 2, 123 (1836); Pax in Engler und Prantl Pflanzenfam. iii, pt. 1 b, 
51 (1889); Portulaceae Jussieu Gen. PI. 312 (1789) partim ; Rouy et Foucaud FI. France iii, 314 (1896). 
Herbs, usually glabrous. Leaves usually alternate, occasionally opposite or subopposite, exstipulate 
or stipulate, usually entire and more or less succulent. Inflorescence usually cymose, terminal or 
axillary, rarely solitary. Flowers monoclinous, usually opening only in bright sunshine, usually 
entomophilous, sometimes self-pollinated or even cleistogamous. Sepals usually 2, rather large, the 
lower one overlapping the upper one. Petals usually 5, separate or more or less coherent. Stamens 
all fertile, usually attached to the base of the petals and opposite to them. Anthers versatile, introrse, 
dehiscing longitudinally. Ovary usually superior (subinferior in Portulaca), with 1 loculus. Style 
united below'. Stigmas 3 — 8 . Seeds 1 — 00, each on a basal funicle, funicles often connate. Embryo 
usually peripheral. Endosperm starchy. Radicle long. 
About 17 or 18 genera and 210 species; cosmopolitan but chiefly American. 
British genera of Portulacaceae 
Genus 1. # Claytonia (see below). Sepals persistent. Corolla actinomorphic, polypetalous. 
Stamens 5. Ovary superior. 
Genus 2. Montia (p. 3). Sepals persistent. Corolla zygomorphic, gamopetalous. Stamens 
usually 3. Ovary superior. 
Genus 3. tP° r t u l aca (p- 6). Sepals caducous above. Corolla actinomorphic, polypetalous. 
Stamens 4 — 00 . Ovary subinferior. 
Genus 1. ^Claytonia 
Claytonia [Gronovius FI. Virg. 25 (1743);] L. Sp. PI. 204 (1753) et Gen. PI. ed. 5, 96 (1754); Pax in 
Engler und Prantl Pflanzenfam. iii, pt. 1 b, 57 (1889); Limnia [L. in Kongl. Sw. Wet. Acad. Ha 7 idl. (Stockholm) 
vii, 130, t. 5 (1746);] Haworth Syn. PI. Succ. 11 (1812) inch Claytonia. 
Perennial or annual herbs. Shoot usually glabrous and more or less succulent. Leaves 
exstipulate ; ground-leaves with long petioles ; stem-leaves alternate or opposite, with petioles 
short or absent. Inflorescence usually terminal. Flowers actinomorphic, protandrous. Sepals 2, ovate, 
persistent. Petals 5, free. Stamens 5, antipetalous, joined to the petals at the base. Ovary superior. 
Ovules few. Fruit a capsule, explosive, 3-valved, globose. Seeds usually 3, compressed. Embryo 
peripheral. 
The genus was named after John Clayton, a botanist of Virginia, and a correspondent of Gronovius. 
About 20 species; northern Asia; northern and central America; Australia, New Zealand. 
1 Probably these structures are really bracteoles ; and if so the perianth should be regarded as monochlamydeous and 
the so-called petals as sepals. 
M. III. 
I 
