92 
Dicotyledons with Incomplete Flowers — Aristolochiacecz . 
Distribution. Confined to South-Eastern Tropical Asia, the Indian Archipelago and Islands of the Indian 
Ocean, including Madagascar. 
Stem remarkable in its internal anatomy from the extraordinary abundance of unrollable spiral vessels. 
Perianth simple, 4-lobed. 
. USES, &c. Pitcher-plants are of no economic importance. Several species, from the singularity of their 
pitchers, are frequently grown in hot-houses. In Nepenthes Rajali , a Bornean species not yet introduced, the pitcher 
is about 1 ft. in length by 6 in. in diameter, with a “ lid” 10 in. by 8 in. 
Natural Order 
EUPHORBIACE^E Tab. 76. 
D iagnosis. —'Herbs shrubs or trees, often with a milky juice. Flowers 
unisexual, achlamydeous monochlamydeous or dichlamydeous. Ovary free, 
3-celled, with i or 2 pendulous ovules in each cell; rarely 2-celled. Seeds 
albuminous. 
Distribution. —A very large and cosmopolitan Natural Order, most numerous in Tropical countries, 
where a large proportion of the species consists of trees or shrubs. The principal genus in Europe, Spurge 
(E^Lphorbla), is common to every quarter of the Globe, and includes about 700 species. Some Tropical 
and Canarian Spurges assume the habit of Cactacese, with succulent, leafless, occasionally spinose stems. 
Number of British Genera, 3 ; Species, 16. 
Leaves usually membranous, alternate or opposite; in Box ( Buxus ) opposite, coriaceous and evergreen; in 
Xylophylla replaced by flattened leaf-like branches, bearing the flowers on their margin. 
. . Flowers naked (achlamydeous) in Spurge ( Euphorbia ), inclosed in a minute cup-shaped involucre, usually one 
pistillate with several staminate flowers, the latter each reduced to a solitary stamen ; the involucre bordered by 
4 or 5 variously shaped, rounded or horned spreading lobes called “ glands in Box {Buxus) flowers in axillary 
