482 SYSTEMATIC BOTANY. 



or capsular, or samaroid, with 2 — 3 valves. Seeds (Fig. 890), 

 usually arillate, exalbuminous; embryo rarely straight, usually 

 curved (fg. 890), or twisted in a spiral direction ; cotyledons 

 sometimes very large ; radicle next the hilum. 



Diagnosis. — Flowers unsymmetrical, hypogynous. Sepals 

 and petals 4—5, imbricated, the latter commonly with an ap- 

 pendage. Stamens never agreeing in number with the sepals 

 and petals, and inserted on a fleshy or glandular disk, or upon 

 the thalamus; anthers bursting longitudinally. Fruit usually 

 consisting of 3 carpels. Seeds commonly 2, sometimes 1 or 3, 

 or very rarely more, exalbuminous, usually arillate and without 

 wings ; embryo almost always curved or spkally twisted. 



Division of the Order, 8fc. — This order is divided into 4 

 sub-orders, as follows : — 



Sub-order 1. Sapindece. Leaves alternate. Ovules usually 

 solitary. Embryo generally cui-ved, or sometimes straight. 

 Examples: — Paullinia, Sapindus, Nephelium. 



Sub-order 2. Hippocastanece. — Leaves opposite. OatiIcs 2 in a 

 cell, of which one is ascending, and the others suspended, 

 (Fig. 714). Embryo curved (Fig. 890), with a small radicle 

 and large fleshy consolidated cotyledons. Examples : — 

 JEsculus, Pavia. 



Sub-order 3. Dudonece. — Leaves alternate. Ovules 2 or 3 in a 

 cell. Embryo spiral. Examples : — Koclreuteria, Dodona^a, 

 Ophiocaryon. 



Sub-order 4. Meliosmece. — Leaves alternate. Flowers very 

 irregular. Stamens 5, 3 of which are abortive, and only 2 

 therefore, fertile. Ovules 2 in a cell, both of which are sus- 

 pended. Fruit a drupe. Embryo folded up. Example : — 

 Meliosma. 



Distribution, 8fc. — Chiefly found in tropical regions, espe- 

 cially those of South America and Lidia; some occur in tem- 

 ])erate climates, but none inhabit the cold northern parts of 

 the globe. There are no native i)lants of this order in Europe. 

 The Horse-chestnut, now so well known in Europe, is only 

 naturalised amongst us. There are about 73 genera, and 

 400 species. 



Properties and Uses One of the most prominent properties 



of the order is the presence of a sajjonaccous principle, from 

 which its name is derived. Many arc poisonous in all their parts ; 

 but it is more frequently the case that, while the root, leaves, 

 and branches are dangerous, the poisonous juice becomes so 

 (liH'uscd throuiiliout their succulent fruits as to render them 

 innocuous, or in other cases, even vahiabic articles of dessert. It 

 sometimes even happens that while tlic pericarp is wholesome, 

 the seeds are dangerous. Some plants of the order arc 

 astringent and aromatic; others are diaphoretic, diuretic, and 



