ANGIOSPERM^, DICOTYLEDONEa 777 



Alliance LYI. — Disciflorse. 



Families: LinacecB, Erythroxylacece, Oxalidacea', Humiriacece, 21alpigkiacece, Zygo- 

 phyUacecB, Qeruniaceoe, Balsaminece, Tropceolacece, Rutacece, Auriantiacece, 

 Diosmacece, Zanthoxylacea', Simarubacece, Ochnaceae, Biirseracece, Meliacece, 

 Ilicinece, Cdastrinece, Bliamnacecc, Avipdidece, SapindacecB, Acerinece, 

 HippocastanecB, Sabiacece, TerebinthacecB. 



Annual smd perennial hei-bs, shrubs, and trees, ■with simple and compound 

 foliage-leaves. Flowers actinomorphic and zygomorphic, hermaphrodite, pseudo- 

 hermaphrodite, moncecious and dicecious; arranged in varying types of ioflores- 

 ceuce. Floral-leaves in two -i-o-merous whorls; the lower whorl a calyx, the upper 

 a corolla. The gynfeceum is composed of a whorl of carpels borne on a swollen 

 disa Ovary superior. Each carpel has a separate loculus. In Aurantiaceae and 

 Ampehde« the carpels are completely united so as to form a single pistil: in 

 Rutacese and ZygophyllacesB they are united at the base and form a lobed ovary, 

 whQst in Zanthoxylacefe, Oehnacefe, and Simarubacese, they are quite separate (see 

 fig. 43S *). In Terebinthacefe only one cai-pel is developed, but there are usually 

 traces of suppressed carpels close to it. The ovules are in the inner angles of the 

 locuH; in Aurantiacese, Rutaceje, and ZygophyUaceje their number exceeds two in 

 each loculus, in the other families it is only 1-2. The stamens are arranged in 1-2 

 whorls, and number 4-5 in each whorl; they spring from the edge or from the 

 surface of the floral receptacle, which is swollen and forms a ring round the ovary; 

 their place of origin is always lower than the base of the ovary (see figs. 438 -■ ^- • ). 

 The poUen is adhesive. The fruit contains either few seeds or a single compara- 

 tively large seed. 



The Disciflorffi are in most instances woody plants, containing etherial oils and 

 aromatic, resinous substances like turpentine. Amongst the Malpighiacese, Celas- 

 tiiae», and Ampelidefe are many lianes. The foliage-leaves are undivided in 

 Erythxoxylaceffi and Celastrinese (see fig. 438^), lobed in most Aceraeese and 

 Ampelideas, and variously segmented and compounded in the other f amili es (see 

 fig. 438*). The petals are usually small, and of a greenish-yeUow colour. The 

 filaments in MeKanthaceae and Aurantiacefe are connate all together, or in groups. 

 The fruits are extremely various. In Staphyleacea? and Diosmace« they are 

 folHcles; in Celastracew and Rutace«, capsules (see %. 325 ^ p. 431); in Zygo- 

 phyUacese, Aceracefe, and Malpighiacese, schizocarps; in the Tree of Heaven, of the 

 family Simambaceae, winged achenes (samaras, see %. 323", p. 42S); and in 

 Ampehdese and Aurantiace*, berries. The Disciflorsfi are distributed over the 

 whole earth. The majority belong to the tropics, and several, e.g. Burserace«, 

 Ochnaceae, and Malpighiacese axe exclusively tropical The Diosmacece are confined 

 to South Africa, the Rutaces to the districts of the Mediterranean and the Black 

 Sea. Ckanparatively few species occur in the Xorthem Temperate Zone, or in 

 corresponding situations on mountains. The Mountain Maple covers about the 



