20 NATURAL ITISTORY OF PLANTS. 



Stamens 4 included. Gynaeceum of Oxybaphvx. Fruit clothed by 

 hardened base of calyx ; wings % marginally dentate, spinulose after- 

 wards reflexed, so as to form an exterior cell, containing 2 series of 

 vertical capitate-glandular tubercles. Seed of Oxybaphm ; embryo 

 folded. — A herb ; leaves opposite ; flowers 3-nate, opposite lobes of 

 gamophyllous 3-fid involucre {Warm and Western America). See p. G. 



8. Boerhaavia L. — Calyx 2-partite to middle ; upper part infundi- 

 buliform or campanulate petaloid, apex 5-lobed, deciduous ; lower 

 part cylindrical or obconical, persisting round the fruit, indurated 

 (virescent or nigrescent), afterwards sometimes slightly gibbous, 

 (Senkcnbergia). Stamens 1-5 connate at the base, often exserted. 

 Germen nearly of Mirabilis ; style erect, sometimes longitudinally sul- 

 cate at back ; apex thickened, stigmatiferous. Fruit and seed nearly 

 of Oxyiaphus ; embryo usually conduplicate. — Herbs annual or peren- 

 nial, or frutescent at base ; leaves opposite ; flowers (small, insig- 

 nificant) in simple or ramified spikes, or generally in cymes ; cymes 

 regular or 1 -lateral, rarely solitary or with few flowers, or reduced to 

 1 ; bracts small, not coloured (All warm regions of the Globe). See p. 7. 



9. Abronia J. — Calyx hypocrateriform ; tube narrow, more or less 

 inflated at base; limb open, sometimes oblique, 5-lobed deciduous. 

 Stamens 5, included, adnate to base of perianth. Germen and ovule of 

 Mirabilis; style subclavate to stigmatiferous apex. Fruit clothed 

 with base of 5-agonal costate calyx, which is dilated into from 3-5 

 wings more or less membranous-venose. Seed of Mirabilis ; second 

 (interior) cotyledon of subcontorted or conduplicate embryo, abortive. 

 — Creeping herbs ; leaves opposite, unequal long-petiolate ; flowers, 

 glomerules, falsely capitate with involucre; usually 5-phyllus, inserted 

 at the summit of the usually elongated peduncle (North Temperate 

 America). See p. 8. 



10. Pisonia Plum. — Flowers dioecious or polygamous ; calyx often 

 coloured, much varied in form, subovoid, campanulate, clavate, or 

 tubular (in the female flowers often longer and more tubular) ; teeth 

 4-6, oftener 5, usually short valvate, or induplicate valvate, more 

 rarely subreduplicate. Stamens 5-10, or more rarely 10-30-40 ; 

 filaments free at the base or slightly connate, usually unequal, either 



