99 BOTANY. 
superior. Trees or shrubs with alternate, stipulate, or exstipulate leaves. . 
Natives chiefly of temperate climates. The order has been divided into the 
following sub-orders : 
Sub-order 1. Cupulifere, the Oak Family. Trees or shrubs with alter- 
nate and simple straight-veined leaves, deciduous stipules, and monoecious 
flowers ; the sterile in catkins (aments or capitate c!ustered in the Beech), the 
fertile solitary or clustered, furnished with an involucre which forms a cup or 
covering to the one-celled, one-seeded nut. Ovary, two- or seven-celled, with 
one or two pendulous anatropous ovules in each cell, but all the cells and 
ovules, except one, disappearing in the fruit. Calyx adherent to the ovary, 
the minute teeth crowning its summit. Seed with no albumen, filled with the 
embryo; cotyledons very thick and fleshy ; radicle short, superior. Examples: . 
Quercus, Castanea, Fagus, Corylus, Carpinus, Ostrya, Lithocarpus. All of 
these, with the exception of the last, have North American species. In oaks 
(Quercus) North America is especially rich, the northern and middle 
States alone possessing twenty species, not to mention numerous others pecu- 
liar to the south and west of the continent. Some of the southern species, as 
the Live Oak (Q. virens), have evergreen leaves. Of Castanea there are 
three species in the United States: the common Chestnut (C. vesca), the 
Chincapin (C. pumila), and a still smaller species, C. nana. The common 
American Beech is Fagus ferrugineus. There are also the Hazelnut (Corylus 
americana and rostrata), the Hornbeam (Carpinus americana), and the Iron- 
wood (Ostrya virginica). 
Sub-order 2. Platanee, the Plane Tribe. Flowers in globose catkins ; 
stamen one, with scales; ovary, one-celled ; style, thick and subulate ; ovules, 
solitary or In pairs; suspended, orthotropal: fruit consisting of compressed 
clavate nuts, terminated by a recurved style: seeds one or two,. pendulous, 
albuminous: radicle, inferior; leaves palmate or toothed, and stipulate. 
Natives chiefly of temperate regions. The principal genus in this family is 
Platanus, represented in the Old World by P. orientalis, the Plane tree, and in 
the New by P. occidentalis, Button-wood, or Sycamore. 
Sub-order 3. Balsamiflua, the Sweet-Gum Tribe. Flowers with 
verticillate bracts or minute scales; anthers, numerous; ovary, two-celled ; 
ovules 00, amphitropal: fruit consisting of two-celled capsules, united together, 
so as to form a hard cone: seeds usually numerous, winged, albuminous ; 
radicle superior ; leaves stipulate. Balsamic trees natives of tropical and 
warm regions. The characteristic genus of this family is Liquidambar, 
embracing three species, two Asiatic and one North American. The latter, L. 
styracifilua, or sweet-gum, is abundant in the south-eastern portion of the 
continent. 
Sub-order 4. Betulinee, the Birch Tribe. Flowers with bracts which are 
sometimes verticillate : ovary, two-celled; ovules solitary, pendulous, 
anatropal: fruit membranous, indehiscent, forming a sort of cone; seeds 
pendulous, radicle superior, leaves with deciduous stipules. Natives of 
temperate and cold regions in Europe, Asia, and America, and extending to 
arctic and antarctic regions. Kxamples: Betula and Alnus. Of Betula, or 
birch, there are numerous species in North America; the most important 
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