This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Shrubs with opposite entire (rarely pinnatifid) leaves, and completely gamopetalous flowers, in dense terminal panicles or thyrses. Calyx campanulate, mostly 4-toothed, persistent. Corolla salverform, the tube cylindric, the limb 4-lobed, the lobes induplicate-valvate. Stamens 2, inserted near the summit of the corolla-tube; filaments short or slender; anthers ovate or oblong. Ovary 2-celled; ovules 2 in each cavity, pendulous; style elongated; stigma 2-cleft. Capsule narrowly oblong, somewhat compressed, coriaceous, loculicidally 2-valved from above, the valves concave. Seeds pendulous, compressed, obliquely winged. [Greek, a pipe, or tube.]
About 12 species, natives of Asia and eastern Europe, the following typical.

Fig. 3313
Syringa vulgaris L. Sp. Pl. 9. 1753.
A glabrous shrub, 10°-25° high with terete branches. Leaves ovate, entire, deciduous, green on both sides, acuminate at the apex, truncate or subcordate at the base, 2'-5' long, 1'-3' wide; petioles 1/2'-1' long; flowers lilac or white, very numerous, 5"-7" long, 4"-,5" broad, in large terminal thyrses; calyx about 1" long; corolla-tube about 1" in diameter; ultimate pedicels short; capsule 8"-12" long, 2" thick.
Escaped from gardens to roadsides, Maine and New Hampshire to eastern New York and Pennsylvania. Native of eastern Europe. Pipe-tree. Pipe-privets. Blue-pipe. Blue-ash. Roman-willow. Flowers fragrant. April-May.
2. FRÀXINUS [Tourn.] L. Sp. Pl. 1057. 1753.
Trees, with opposite and in all our species odd-pinnate leaves, and small dioecious or polygamous (rarely perfect) greenish fasciculate or racemose-fasciculate flowers, appearing before or with the leaves from the axils of those of the previous season. Calyx small, 4-cleft, irregularly toothed, entire or none. Petals none or 2-4, separate, or united in pairs at the base, induplicate-valvate. Stamens 2 (rarely 3 or 4), inserted on the base of the petals or hypogynous; filaments short or elongated; anthers ovate, oblong or linear. Ovules 2 in each cavity of the ovary, pendulous; stigma 2-cleft. Fruit a flat samara, winged at the apex only or all around, usually I-seeded. Seed oblong, pendulous. [The ancient Latin name.]
About 50 species, mostly of the north temperate zone. Besides the following, about 12 others occur in the Southern and Western States. Type species: Fraxinus excelsior L.
Lateral leaflets stalked; calyx mostly present, at least in the fertile flowers. | ||
Body of the samara terete or nearly so, the wing chiefly terminal. | ||
Wing almost entirely terminal; leaves pale beneath. | ||
Twigs and leaves glabrous, or leaves pubescent beneath. | 1. | F. americana. |
Twigs and leaves densely pubescent. | 2. | F. biltmoreana. |
Wing manifestly extending down on the sides of the body. | ||
Wing of the samara long-linear, about 2" wide. | 3. | F. Darlingtonii |
Wing of the samara spatulate or oblong-spatulate, mostly 3"-s" wide. | ||
Samara-body terete, slender. | ||
Samaras broadly spatulate; leaves firm, entire. | F. Michauxii. |
Samaras narrowly spatulate; leaves thin, serrate or entire. | 5. | F. pennsylvanica. |
Samara-body compressed; leaflets entire. | 6. | F. profunda. |
Body of the samara flat, the wing extending all around it. | ||
Twigs terete; leaflets 5-7; samara elliptic or spatulate. | 7. | F. caroliniana. |
Twigs 4-sided; leaflets 7-11; samara oblong or cuneate. | 8. | F. quadrangulata. |
Lateral leaflets sessile: calyx none; samara winged all around. | 9. | F. nigra. |
 
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