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GROUPS AND ORDERS OF APETALOUS EXOGENS. 



Subclass III. Apetalous Exogenous Plants. 



Corolla none ; the floral envelopes consisting of a single series (which is 

 regarded as calyx, but often called perigonium ), or sometimes entirely 

 wanting (or achlamydeous). 



CONSPECTUS OP THE GROUPS AND ORDERS. 



Group 1. Flowers perfect, with a conspicuous or colored calyx. Ovary several-celled, many-ovulcd. Capsule or berry 



many-seeded. — Herbs or climbing shrubs. 

 Order 82. Aristolochiace^;. Calyx often petaloid ; the aestivation valvate. Stamens adherent to the base of the 

 style : stigmas radiate. Capsule or berry 3 - G-celled, many-seeded. 



Group 2. Flowers perfect or rarely polygamous, with a regular and often petaloid calyx : ovules solitary in each ovary 

 or cell. Embryo curved around mealy albumen, rarely in the axis. — Chiefly herbs. 

 * Ovary one-celled, with a single ovule. 



83. Chenopodiace^:. Calyx persistent ; the stamens as many as its lobes, or fewer, and inserted at their base. 



Fruit an utricle. — Chiefly weed-like herbs, with small flowers. 



84. Amarantiiace^e. Calyx of 3 - 5 dry scarious sepals. Stamens 5 or more, distinct or monadelphous, hypo- 



gynous : anthers often one-celled. Fruit an utricle. — Herbs; the flowers imbricated with scarious 

 bracts. 



85. Polygonace2e. Stamens inserted on the calyx. Fruit a caryopsis or achenium, compressed or triangular. 



Embryo curved or sometimes nearly straight, on the outside (rarely in the midst) of starchy albumen. 

 — Herbs, with sheathing stipules (ochreae). 



** Ovary compound, consisting of a whorl of several one-seeded carpels. 

 8G. Phytolaccace«. Berry 7 - 10-celled ; the cells 1-seeded. 



Group 3. Flowers perfect or sometimes polygamous, not disposed in aments. Calyx regular and often petaloid. Ovary 

 1- (rarely 2-) celled, with a solitary ovule, or but one in each cell. Embryo not coiled around albumen. — 

 Trees or shrubs, rarely herbs. 



87. LAURACEiE. Calyx of 4 - 6 somewhat united sepals, in a double series, free from the ovary. Stamens usually 



more numerous than the sepals : anthers opening by recurved valves. Fruit a berry or drupe. — 

 Trees or shrubs. 



88. Santalaceje. Calyx-tube adherent to the ovary ; the limb valvate; the base lined with a fleshy often lobed 



disk. Stamens opposite the lobes of the calyx. Ovary one-celled. Fruit indehiscent, crowned with 

 the limb of the calyx. Seeds albuminous. — Trees, shrubs, or sometimes herbs. Leaves alternate, 

 entire. 



89. Thybielace^e. Calyx petaloid, imbricated in aestivation ; the tube free. Stamens often twice as many as the 



lobes of the calyx. Ovary with a single pendulous ovule. Seed without albumen. — Shrubs with 

 a tough bark. 



90. Eleagnaces:. Flowers mostly dioecious. Calyx-tube free. Stamens as many as the calyx-lobes and alternate 



with them, or twice as many. Ovary one-celled, with a single erect ovule. Fruit an achenium, 

 enclosed in the berry-like calyx-tube. Seeds albuminous. — Shrubs ; the foliage and branches scaly. 



91. UlMACEiE. Calyx free from the ovary, 4 - 5-cleft, imbricated in aestivation. Ovary 1 - 2-celled, with a single 



suspended ovule in each cell : styles or stigmas 2. Fruit a samara or drupe. — Trees or shrubs, with 

 rough alternate leaves, and small flowers in axillary clusters. 

 Group 4. Flowers perfect, destitute of both calyx and corolla. Embryo minute, included in the persistent sac of the 

 amnios at the apex of the albumen. — Herbs or somewhat shrubby plants. 



92. Saururace^;. Stamens definite. Ovary of 3 - 5 partly united carpels, each with few ascending ovules. Fruit 



dry or somewhat baccate, with one or few seeds in each carpel. — Herbs with alternate entire leaves, 

 and flowers in racemes or spikes. 



