182 BOTANY. 
in number to the lobes of the calyx, with which they alternate; rarely 
wanting. Stamens generally eight, inserted on a hypogynous disk. Ovary 
tree, two-lobed, two-celled ; ovules in pairs ; amphitropal, pendulous; style 
one ; stigmas two. Fruit, a samara, composed of two winged carpels, each 
one-celled, with one to two seeds. Seeds erect, exalbuminous; embryo 
curved, with foliaceous cotyledons, and the radicle next the hilum. Trees 
with opposite, simple, lobed or palmate, exstipulate leaves. Flowers often 
polygamous. They are confined chiefly to the temperate parts of Europe, 
Asia, and North America. They yield a saccharine sap, from which sugar 
is sometimes manufactured. Acer saccharinum is the Sugar Maple of 
America. Acer pseudo-platanus, the Sycamore or Great Maple (the Plane- 
tree of Scotland), acts well as a shelter or break-wind in exposed places, as 
near the sea. Its sap is slightly saccharine. Its wood is used in machinery 
and for charcoal. The leaves are often covered with black spots, caused 
by the attack of a fungus, Xyloma or Rytisma acerinum. ‘There are three 
known genera, and sixty species. Examples: Acer, Negundo, Dobinea. 
Of these genera, the two first with thirteen species are North American. 
Acer pseudo-platanus (Europe) (pl. 67, jfig.1); a, a flowering braneh ; 
b, a male; c, female flower ; d, the winged haere ; é, the seed. 
ORDER 189, Matrieutaces, the Malpighia Figcsalge Sepals five, sligihide 
united, persistent, often oso at the base; estivation imbricated. 
Petals five, unguiculate, with convolute eens Stamens usually ten, 
often monadelphous; anthers roundish, with a projecting process from the 
connective. Ovary formed by three (rarely two or four) carpels, more or 
less combined ; ovules solitary, with a long pendulous cord; styles three, 
distinct or united. Fruit dry or fleshy, sometimes winged. Seeds solitary, 
orthotropal, suspended, exalbuminous; embryo straight or curved in various 
ways; cotyledons foliaceous or thickish. Trees or shrubs, sometimes 
climbing, with simple, opposite, or very rarely alternate, stipulate leaves 
without dots.. Hairs, when present, peltate. Flowers either perfect or 
unisexual. They are inhabitants of tropical countries chiefly, and a great 
number of them are found in South America. Lindley notices forty-two 
yenera, including 555 species. 
Section A. Diplostemones. Number of stamens always double that of 
petals, some of them occasionally sterile. Styles usually two tothree. The 
same number of ovaries united. Flowers of one form only. 
Tribe 1. Malprghiee. Fruit wingless. Example: Malpighia. 
Tribe 2. Banisteriee. Carpels provided with wings, the dorsal solely or 
most developed. Example: Lophopterys. 
Tribe 3. Hiree. Carpels winged ; the marginal solely or most developed. 
Example : Molina. 
Section B. Meiostemones. The whole or part of the alternipetalous 
stamens wanting. Style single by the abortion of two others. Ovaries 
distinct. Flowers of two different forms on the same. plant. 
Tribe 4. Gaudichaudiee. Carpels with or without wings. Example: 
(raudichaudia. 
182 
