171 



Affinities. It is not easy to fix with precision the relative position of 

 .this order : I formerly thought it related to Hydrangese, chiefly on account 

 of the striking resemblance in the areolations of the seeds, and the irregu- 

 larity of the flowers. It is probable, however, that more importance should 

 be attributed to the acid juice and membranous large stipulse, in which case 

 Begoniaceye are most nearly related to Polygonese, many of which have a 

 coloured calyx and 3-corncred fruit ; from which they dift'er in the structure 

 of the fruit and seed. Link places them near Umbelliferse ; but I know not 

 upon what grounds. 



Geography. Common in the West Indies, South America, and the 

 East Indies. Mr. Brown remarks, that no species has been found on the 

 continent of Africa, though several have been found in Madagascar and the 

 Isles of France and Bourbon, and I in the island of Johanna. Congo, 464. 



Properties. The roots are astringent and slightly bitter. Those of 

 2 species are used in Peru with success in cases of a flux of blood, or in 

 other visceral diseases in which astringents are employed. They are also 

 said to be useful in cases of scurvy, and in certain fevers. . 



Example. Begronia. 



CLVIII. NYCTAGlNEiE. The Marvel of Peru Tribe. 



NycTAGiNES, Jms. Gen. 90. (1789) ; R. Brown Prodr. 421. (1810.) 



Diagnosis. Apetalous dicotyledons, with definite ascending ovula, an 

 inferior tubular (often coloured) calyx hardening at the base, hypogynous 

 stamens, and embryo surrounding floury albumen. 



Anomalies, 



Essential Character. — Calyx tubular, somewhat coloured, contracted in the 

 middle ; its limb entire or toothed, plaited in aestivation, becoming- indurated at the base. 

 Stamens definite, hypogynous ; anthers 2-celled. Ovary superior, with a single erect ovu- 

 lum ; style 1 ; stigma 1. Fruit a thin utricle, enclosed within the enlarged persistent tube 

 of the calyx. Seed without its proper integuments, its testa being coherent with the 

 utricle ; embryo with foliaceous cotyledons, wrapping round floury albumen ; radicle infe- 

 rior ; plumula inconspicuous Stem either herbaceous, shrubby, or arborescent. Leaves 



opposite, and almost always unequal ; sometimes alternate. Flowers axillary or terminal, 

 clustered or solitary, having an involucrum which is either common or proper, in one piece 

 or in several pieces, sometimes minute. 



Affinities. The tubular calyx, the limb of which is plaited in aestiva- 

 tion, and the base of which becomes hardened round the ovarium, so that 

 it resembles a woody pericarp, will, if taken with the curved embryo and 

 farinaceous albumen, at all times distinguish Nyctagineas ; add to which, the 

 articulations are tumid, as in Geraniacese. Its nearest affinity is perhaps 

 with Polygonege, from which.it, however, differs so much that it need not be 

 compared with them. 



Geography. Natives of the warmer parts of the world in either hemi- 

 sphere, scarcely extending far beyond the tropics, except in the case of the 

 Abronias found in North-west America. 



Properties. In consequence of the generally purgative ({uality of the 

 roots of species of this family, one of them was supposed to have been the 

 true jalap plant, which is, however, now known to be a mistake. The flowers 

 of several species of Mirabilis are handsome, as are those also of some of 

 the Abronias ; but the greater part of the order is composed of obscure weeds. 

 The genus Pisonia consists of trees or shrubby plants. 



Examples. Mirabilis, Boerhaavia, Oxybaphus. 



