10 THE TUBEROUS BEGONIA. 



A BRIEF SKETCH OF THE BEGONIA 

 FAMILY. 



?HE Begonia family consists of some 350 or more species, -which are being 

 added to from time to time as new discoveries are made. It consists 

 of two genera, but with one exception all are species of Begonia, and are 

 distributed through tropical America, Asia (chiefly on the other side of the 

 Ganges), and in tropical and sub-tropical South Africa ; in all of which countries 

 they grow in great abundance. Few are found in the islands of the Pacific 

 Ocean, and, so far as is at present known, no species are indigenous to Australia. 

 The Begonias, as a natural group or family, stand isolated as it were from even 

 the nearest of their allies in the vegetable kingdom, forming a very characteristic 

 and readily recognised class of plants, with succulent or sub -shrubby stems, 

 reduced to a short fleshy tuber, as in the tuberous-rooted group, or have some- 

 what scandent or climbing stems, as in B. glaucophylla or B. fagifolia, which cling 

 to a wall or other moist surface by means of numerous roots which they throw 

 out. Their other characteristics consist of stipulate, generally ornamental leaves, 

 mostly oblique at the base ; irregular or unsymmetrical monoscious flowers, that 

 is, there are male and female blooms on the same plant ; numerous free or mona- 

 delphous stamens, that is, united in one bundle ; and an inferior three rarely 

 two four or many-celled ovary, with numerous minute seeds scattered over a 

 very much enlarged entire or bifid placenta that projects into the cavity of the 

 seed-vessel. The fruit is a trigonous or sometimes winged capsule, and rarely 

 fleshy, resembling a berry.. The nearest allies of this family are four species 

 constituting the Datisca family, with which they agree in the structure of the 

 seeds, ovary, and unisexual flowers. There is also a slight apparent affinity 

 between the order and those of the Cucumber family, the Passion Flowers, and 

 the Saxifrages. 



THE ESSENTIAL CHARACTERS OF THE GENUS BEGONIA. 

 THESE are that the perianth is irregular, and usually, if not always, coloured 

 like a corolla, consisting in the male flowers of four sepals in two series, rarely 

 more or fewer ; and in the female flowers of five spirally arranged, imbricating 

 sepals. The stamens are numerous and free, or united into a more or less 

 elongated bundle, and occupy the axis of the flower. The ovary is inferior, that 

 is, wholly sunk in the receptacle or top of the flower stalk, which is adnate to it, 

 so that the sepals appear to spring from the top of it ; three rarely one, two 

 four, or five-celled ; styles equalling the cells in number, free or united at the 

 base, and more or less deeply two-lobed or divided ; placentas axile, rarely 

 parietal. The three-angled or often winged fruit is a capsule opening at the 



