962 
POLYPETALOUS OKDERS. 
calyx upon which the stamens are inserted ; pi, the pistil ; /, the 2-celled anther 
with the upper part of the filament ; o, the ovar j cut vertically ; s, fruit ; b, verti- 
cal section of a carpel ; m, horizontal section of the exalbuminous seed ; n, the em 
brjo which fills the entire seed. 
446. Calycanthace^, the Calycanthus Trihe. — Shrubs with 
quadrangular stems (which exhibit when old 4 axes of growth 
surrounding the old wood). Leaves opposite, without stipules. 
Sepals and petals confounded. Stamens numerous ; anthers 
adnate, extrorse. Ovaries indefinite, simple, 1-celled. Fruit 
consisting of achsenia, inclosed in the fleshy tube of the calyx. 
Seeds without albumen ; embryo straight. 
Genus. — Calycanthus. 
447. Myrtace^, the Myrtle Tribe. — Trees or shrubs. Leaves 
opposite, entire, and dotted, without stipules. Calyx adherent 
to the ovary ; limb 4 or 5 cleft. Petals 4 or 6, or wanting. 
Stamens indefinite; filaments long; anthers ovate. Ovary 
1-6-celled ; ovules pendulous or erect. Seeds numerous, with- 
out albumen ; embryo straight or curved. 
a. Properties : these plants abound in an aromatic volatile oil and an astringent 
piinciple. 
Genus. — Myrtus, Punica, 
448. MELASTOMACEiE, the Melastoma Tribe. — Trees^ shrubs^ or 
herbs. Leaves opposite, ribbed. Flowers showy. Sepals 4, 5, 
or 6, more or less united. Stamiens as many, or twice as many 
as the petals ; anthers opening by pores, infiexed in aestivation. 
Ova/ry adherent to the tube of the calyx. Fruit capsular or 
euccident. Seeds attached to central placentae, exalbuminous ; 
embryo straight or curved. 
a. Properties : the berries of Melastoma are edible. 
Genus. — Rhexia, Melastoma 
449. Lythrace^, the Loosestrife Tribe. — Herbs and shrubs, 
Lea/ves opposite, entire. Calyx tubular, lobed ; sometimes the 
lobes have intermediate lobes or teeth. Petals inserted into 
the calyx, alternate with its primary lobes, deciduous. Sta- 
mens inserted into the tube of the calyx below the petals. 
Ovary 2-4-celled ; styles united into one. Fruit a capsule. 
Seeds numerous, exalbuminous, attached to a central placenta ; 
embryo straight. 
a. Properties : astringent useful for dyeing 
Genera. — Lythrum, Cuphea, Ammannia, Decodon. 
450. Rhizophoeace^, the Mangrove Tribe. — Trees or shrubs. 
Leaves simple, opposite, with inter-petiolary stipules. Calyai 
adherent, 4-12-lobed. Petals alternate with the lobes of the 
calyx. Stamiens twice or thrice as many as the petals with 
which they are inserted. Ovary 2-celled ; ovules 2 in each coll, 
