83 



Elje Crcasitirp of Botany 



ARAC 



■ name. The genus gives its name to the 



j order Aquilariacew, and is characterized 

 by a top-shaped leathery calyx, downy ex- 

 ternally, whose limb is divided into five 

 small oblong, reflexed segments ; from 

 the throat of the calyx project ten woolly 

 scales, which adhere to the whole length 

 1 1 of the interior of the calyx tube, and alter- 

 nate with the ten stamens, the filaments of 

 which also adhere for nearly their whole 

 length to the calyx tube, and are attached 

 to the back of the anthers below their 



: middle. The ovary is two-celled, each cell 

 containing a single ovule, suspended from 



: the placenta; these ovules are flat on one 

 side, convex on the other, and winged, the 

 wing being prolonged downwards into a 

 horn-like process ; the ovary is surmounted 

 by a short style, terminated by a large 

 round stigma, which is depressed in the 

 centre. A. Agallocha, k large tree, inhabiting 

 Silhet, and provided with alternate lance- 

 shaped stalked leaves, furnishes an odo- 

 riferous wood, called Aloes- wood, or Eagle- 

 wood, supposed to be the aloes-wood of 

 Scripture. The wood contains an abund- 

 ance of resin, and an essential oil, which is 

 separated, and highly esteemed as a per- 

 fume. The Orientals burn it in their tem- 

 ples for the sake of its slight fragrance, on 

 which account also it was used in the palace 

 of Xapoleon the First. It has been pre- 

 scribed in rheumatic affections in Europe. 

 Other but inferior kinds of this wood are 

 said to be furnished by species of Aloexy- 



i lum and Exccecaria. [M. T. M.] 



AQUILARIACEJE (Aquilariads) consist 

 of fragrant tropical Asiatic trees, with 

 small apetalous flowers, resembling those 

 of a Rhamnus. Only ten species are 

 known, of which the most important is 

 : the genus Aquilaria : which see. 



AQUILEGIA. A genus of Ranunculacece, 

 widely distributed over the temperate 

 regions of the northern hemisphere. It is 

 generally considered to consist of many 

 species, but the authors of the Flora Indica 

 believe that the greater number of these 

 are merely varieties. It is distinguished 

 , by the curious structure of the flowers, 

 which have five fiat, elliptical coloured 

 sepals, alternating with as many spurred 

 petals : the spurs are very large, and pro- 

 duced backwards into hollow tubes, like 

 a cornucopia with the mouth downward, 

 and are frequently curved round towards 

 the central axis of the flower at the ex- 

 tremity. The fruit consists of five f ollicles, 

 with numerous seeds. In cultivation, 

 double varieties occur, which have a sei-ies 

 of spurred petals, with the spurs included 

 in those of the exterior ones, like a nest of 

 crucibles. Stellate varieties also occur, 

 which have the petals flat, and destitute of 

 a spur. The flowers are drooping, unless 

 A. ■parviflwa, which Ledebour describes 

 ; with the flowers perfectly erect, be an 

 ' exception. The five-spurred petals with in- 

 curved heads have been compared to five 

 doves, the sepals representing the wings, 

 | and to this the English name Columbine 

 I refers. The leaves are ternate. the root- 



leaves twice or thrice-ternate. A. vulgaris, 

 the Common Columbine, is apparently na- 

 tive in Britain. It has the flowers usually 

 purplish blue, but in cultivation they vary 

 much, being dark purple, dull reddish, or 

 white. A. alpina has much larger flowers 

 and shorter spurs, and stamens hardly ex- 

 ceeding the petals. A. canadensis has 

 scarlet and yellow flowers, with very long 

 slender straight spurs, and very long sta- 

 mens. The species are quite hardy in the 

 open border. [J. T. S.] 



ARABETTE. (Fr.) Arabis. 



ARABIS. An extensive genus of annual 

 or perennial herbaceous plants, belonging 

 to the natural order Cruciferce, and bearing 

 white, or (rarely) purple flowers. For the 

 most part they are under a foot in height, 

 the root-leaves are stalked, but the upper 

 ones clasp the stem, and all are more or 

 less thickly set with forked hairs. They 

 inhabit various countries, but the British 

 species possess little interest. The name 

 Arabis was probably given to the genus 

 because most of the species delight in 

 stony or sandy soil, such as that of Arabia 

 is presumed to be : Wall-cress, the English 

 name, has similar reference to the usual 

 place of growth. Many species are well 

 adapted for rock-work, and others are 

 equally fitted to be grown as border 

 flowers, as they bloom earlier than most 

 garden plants. The genus being closely 

 allied with others, some confusion exists 

 as to the names severally assigned to the 

 plants which it contains. Some species 

 are described under the names of Turrit is 

 and Cardamine. [C. A. J.] 



ARACA. A name given to the fruit of 

 some Brazilian Eugenias. 



ARACEiE (Aroidece, Arads) are incom- 

 plete plants of the Endogenous class, with 

 numerous naked unisexual flowers, closely 

 packed upon a spadix, shielded when young 

 by the hooded leaf called a spathe, as is 

 seen in the common wake-robin (Arum 

 maculatum). They are common in tropical 

 countries, but rare in those with a cold or 

 temperate climate. Botanists have mixed 

 them with Orontiads, from which their 

 hermaphrodite flowers distinguish them. 

 Most have tuberous roots (corms;, but 

 some acquire the stature of little trees, 

 the most interesting of which is the 

 Dumb-cane, a species of the genus Dieffen- 

 bachia. The acrid poisonous qualities 

 which have given rise to the latter name 

 are characteristic of the order. Neverthe- 

 less the whole contain starch in such 

 abundance that it may be separated in the 

 form of arrowroot or used as food in its 

 combined state ; only, however, after care- 

 ful washing to remove the acrid juices. 

 Thus, the common spotted Arum was eaten 

 with us in time of scarcity, and yields a kind 

 of arrowroot, and the Colocasias are grown 

 everywhere in hot countries as common 

 field crops. See all these names. Among 

 the peculiarities of the order is to extend 

 the end of the spadix into a soft, cellular, 



