Euphorbia. | EUPHORBIACEZ. 627 
like inyolucre). Perianth generally simple and calycine, but often 
wanting, rarely double, the inner of 4-5 minute petals. Stamens 1 
to many; anthers 2-celled. Ovary superior, of 3 (rarely 2 or more 
than 3) united carpels; styles as many as the carpels, free or 
united, entire or divided; ovules 1 or 2 to each carpel, pendulous 
from the inner angle of the cell. Fruit either a capsule of 2-valved 
1-2-seeded cocci separating from a persistent axis, or a 1-3-celled 
drupe, or of 1 or more combined nuts. Seed laterally attached at 
or above the middle of the cell; embryo straight, in the axis of 
fleshy albumen, cotyledons flat, radicle superior. 
‘A large order, of about 200 genera and 3000 species, most abundant in the 
tropics, rare in very cold climates. Many species are poisonous, and a con- 
siderable number yield medicinal products, as castor-oil, croton-oil, gum 
euphorbium, &c. Others afford a wholesome food, as the manioc and tapioca. 
Of the 4 genera found in New Zealand, one (Huphorbia) has a worldwide 
distribution ; another (Poranthera) is found elsewhere only in Australia. The 
two remaining (Alewrites and Homalanthus) have their headquarters in the 
Pacific islands, but extend northwards to China and the Malay Archipelago. 
* Flowers without a perianth, several males and one 
female in a cup-shaped calyx-like involucre .. .. 1. HUPHORBIA. 
** Flowers provided with a perianth. 
Low-growing herbs. Flowers in terminal racemes or 
heads. Anthers opening by pores 3% ; 
Trees with digitately lobed or veined leaves. Flowers in 
terminal cymes. Fruit large, somewhat fleshy, with 
1-3 large oily seeds 3c sc Ne ; 
Trees. Flowers in slender racemes; males numerous, 
females few at the base of the raceme. Fruit cap- 
sular Ae 
2, PORANTHERA, 
3. ALEURITES. 
4, HoMALANTHUS. 
1. HUPHORBIA, Linn. 
Herbs or shrubs abounding in milky juice. Inflorescence of 
numerous males and a single female flower crowded in a small 
cup-shaped 4-5-lobed calyx-like involucre, the lobes usually alter- 
pating with as many fleshy glands, which often possess a white or 
coloured spreading limb. Male flowers consisting of a pedicelled 
stamen without floral envelopes of any kind; anther-cells globose. 
Female flower central in the involucre, of a long-pedicelled 3-celled 
ovary, also without floral envelopes; styles 3; ovules solitary in 
each cell. Capsule 3-lobed, splitting into 3 2-valved cocci, which 
fall away from a persistent axis. 
A vast genus of worldwide distribution, very feebly represented in New 
Zealand. There are probably more than 600 species, of very diversified habit 
and characters. Several species from the Northern Hemisphere are naturalised 
in New Zealand, the most common being the milkweed, H. Peplus, a small 
glabrous annual branched from the base, with thin obovate entire leaves, an 
umbel of 2-3 repeatedly divided rays, smooth capsules, and pitted seeds. 
