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CXLIX. NITRARIACEjE. 



Diagnosis. Polypetalous dicotyledons, with perigynous stamens, concrete 

 carpella, a superior ovarium of several cells, a deeply-divided calyx, regular 

 flowers, an inflexed valvular aestivation, a terminal single style, pendulous ex- 

 albuminous seeds, and a straight embryo. 



Anomalies. 



Essential Character. — Calyx inferior, 5-toothed, fleshy. Corolla of 6 petals, which arise 

 from the calyx, with an inflexed valvular aestivation. Stamens 3 times the number of the pe- 

 tals, perigynous; anthers innate, with 2 oblique longitudinal lines of dehiscence. Ovarium su- 

 perior, 3, or more celled, with a continuous fleshy style at the apex of which are as many stig- 

 matic lines as there are cells ; ovula pendulous, by means of a long- funiculus. Fruit drupaceous, 

 opening by 3 or 6 valves. Seeds solitary, with no albumen, and a straight embryo, with the 

 radicle next the hilum. — Shrubs with deciduous succulent alternate leaves, which are sometimes 

 fascicled. F'lowers in cymes, or solitary. 



Affinities. I take Nitraria to be the type of an order related on the one 

 hand to Ficoideae, and on the other to Rhamneae, agreeing with both in a multi- 

 tude of characters, and with the latter in habit. Decandolle includes Nitraria 

 and Reaumuria among his Ficoideae spuriaa, at the same time expressing a 

 doubt whether they belong either to that or the same order. To me it appears 

 that the affinities of Reaumuria are greater with Hypericum, and I accordingly 

 adopt Dr. Ehrenberg's proposed separation of that genus along with Hololachna, 

 the Tamarix songarica of Pallas, into a little order to be called Reaumurieae. 

 The affinity of Nitraria with Ficoideae is undoubtedly great, especially with Te- 

 tragonia ; but its very different embryo, and the peculiar aestivation of the pe- 

 tals, which is much more like that of Rhamneae, remove it from that order. 



Geography. Natives of western Asia and the north of Africa. One spe- 

 cies is described from New Holland. 



Properties. Slightly saline. Otherwise unknown. 



Example. Nitraria. 



CL. ILLECEBRE^E. 



HernIabijE, Cat. Hort.Par. (1777).— IllecebrejE, R. Brown Prodromus, 413. (1810); Lindt. 

 Synops. 60. (1829).— Paronvchieje, Aug. St. Hit. Mem. Plac. lib. p. 56. (1815) ; Juss. Mem, 

 Mils. 1. 387. (1815) ; Dec. Prodr. 3. 365. (1828) ; Memoire sur les Paronych. (1829.) 



Diagnosis. Polypetalous dicotyledons, with perigynous stamens opposite 

 the 5 sepals, minute petals, concrete carpella, a 1-celled ovarium, and leaves 

 with scanous stipuke. 



Anomalies. Petals very often wanting. Stamens sometimes hypogynous, 



Essential Character. — Sepals 5, seldom 3 or 4, sometimes distinct, sometimes cohering 

 more or less. Petals minute, inserted upon the calyx between the lobes, occasionally wanting. 

 Stamens perigynous, exactly opposite the sepals, if equal to them in number, sometimes fewer 

 by abortion ; filaments distinct; anthers 2-celled. Ovarium superior ; styles 2 or 3, either dis- 

 tinct or partially combined. Fruit small, dry, 1-celled, either indehiscent, or opening with 3 

 valves. Seeds either numerous, upon a free central placenta, or solitary and pendulous from 

 a funiculus originating in the base of the cavity of the fruit ; albumen farinaceous ; embryo 

 lying on one si3e of the albumen, curved more or less, with the radicle always pointing to the 

 hilum j cotyledons small. — Herbaceous or half-shrubby branching plants, with opposite or al- 

 ternate, often fascicled, sessile, entire leaves, and scarious stipule. Flowers minute, wifh sca- 

 rious bracteae. 



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