SI 
Order LX. ACERACEiE. The Sycamore Tribe. 
Acera, Juss. Gen. 50. (1789) ; Ann. Mus. 18. 477. (1811). — AcERiNEi®, DC. Thtorie, 
ed. 2. 244. (1819) ; Prodr. 1. 593. (1824) ; Lindl. Synops. 55. (1829). 
'• Essential Character. — Calyx divided into 5, or occasionally from 4 to 9 parts, with 
an imbricated aestivation. Petals equal in number to the lobes of the calyx, inserted 
round an hypogynous disk. Stamens inserted upon an hypogynous disk, generally 8, not 
often any other number, always definite. Ovary 2-lobed ; style 1 ; stigmas 2. Fruit formed 
of two parts, which are indehiscent and samaroid; each 1-celled, with 1 or 2 seeds. Seeds 
erect, with a thickened lining to the testa; albumen none; embryo curved, with foliaceous 
wrinkled cotyledons, and an inferior radicle. — Trees. Leaves opposite, simple, rarely pin- 
nate, without stipules. Flowers often polygamous, sometimes apetalous, in axillary corymbs 
or racemes. 
Affinities. They chiefly differ from Sapindacese in their fruit having but 
2 carpels, the petals never being furnished with scales, and their opposite leaves. 
Geissois, referred to .Cunoniacese by Don, agrees with this order in habit, 
hypogynous stamens, chcarpellary fruit, and unsymmetrical flowers; but is 
apetalous and polyspermous, and has stipules. The internal structure of its 
seeds is unknown. 
Geography. Europe, the temperate parts of Asia, the north of India, and 
North America, are the stations of this order, which is unknown in Africa and 
the southern hemisphere. 
Properties. Tlie species are only known for the sugary sap of Acer sac- 
charinum and others, from which sugar is extracted in abundance, and for 
their light useful timber. 
GENERA. 
Acer, L. Dobinaea, Hamilt. 
Negundium, Raf. 
? Geissois, Lab. 
Order LXI. SAPINDACE^. The Soap-Tree Tribe. 
Sapindi, Juss. Gen. 246. (1789). — SAPiNDACEiE, Juss. Ann. Mus. 18. 476. (1811); 
DC. Prodr. 1. 601. (1824); Cambessedes in Mem. Mus. 18. 1. (1829). 
Essential Character. — Flowers polygamous. Males. Calyx more or less deeply 
4-5-parted, or 4-5-leaved ; with an imbricated aestivation. Petals 4-5, or occasionally 
absent, alternate with the sepals, hypogynous, sometimes naked, sometimes with a doubled 
appendage in the inside; aestivation imbricated. Disk fleshy; sometimes occupying the 
base of the calyx, regular, nearly entire, expanded between the petals and stamens ; some- 
times glandular, incomplete, the glands stationed between the petals and stamens. Stamens 
8-10, rarely 5-6-7, very seldom 20, sometimes inserted into the disk, sometimes into the 
receptacle between the glands and the pistil ; filaments free or combined just at the base ; 
anthers turned inwards, bursting longitudinally. Rudiment of a pistil very small or none. 
Hermaphrodite Flowers. Calyx, petals, disk, stamens, as in the males. Ovary 3- 
celled, rarely, 2-4-celled, the cells containing 1, 2, 3, very seldom more, ovules. Style 
undivided, or more or less deeply 2- or 3 -cleft. Ovules when solitary erect or ascending, 
rarely (as in Hypelate) suspended ; when double the upper ascending, the lower suspended. 
Fruit sometimes capsular, 2-3-valved, sometimes samaroid, sometimes fleshy and inde- 
hiscent. Seeds usually with an aril ; their outer integument crustaceous or membranous, 
their interior pellucid. Albumen 0. Embryo seldom straight, usually curved, or spirally 
twisted. Radicle next the hilum. Cotyledons incumbent, sometimes combined into a 
thick mass. Plumule 2-lcaved. — Trees, or shrubs which often ciiiiib and have tendrils, 
G 
