EpOoUum.] XXVII. ONAGRACE^. 153 



Along alpine rills, and wet places in the high mountain-ranges or 

 Arctic regions of Europe, Russian Asia, and northern America. Abun- 

 dant in the Scotch Highlands, but very local in England, and does not 

 extend into Wales or Ireland. Fl. summer. 



II. (ENOTHERA. (ENOTHERA. 



Herbs or undershrubs, with alternate leaves, and yellow, red, or purple 

 flowers, either axillary or in terminal spikes or racemes. Calyx-tube 

 prolonged above the ovary, 4-lobed at the top. Petals 4. Stamens 8. 

 Ovary and capsule 4 -celled. Style distinct, with a capitate or 4-lobed 

 stigma. Seeds numerous, without any tuft of cottony hairs. 



A large American, and chiefly North American genus, from whence 

 several species are cultivated in our flower-gardens. 



1. CE. biennis, Linn. (fig. 351). Evening Primrose. A biennial, 2 or 



3 feet high ; the stems almost simple, and more or less hairy ; leaves 

 ovate-lanceolate or lanceolate, slightly toothed, hoary or downy. 

 Flowers yellow, large, and fragrant, in a long, terminal spike, often 

 leafy at the base. Ovary sessile, about 6 to 8 lines long, the tube of 

 the calyx at least an inch longer, the petals broad and spreading. 

 Capsule oblong. 



A North American plant, long cultivated in European flower-gardens, 

 and now naturalised on river banks and other sandy places in western 

 Europe. Apparently fully established in Lancashire and some other 

 counties of England. Fl. summer and autumn, opening in the evening. 



[CE. odorata, Jacq., which has linear-lanceolate waved leaves and a 

 long cylindric capsule, is a Patagonian species, recently established on 

 the S.W. coasts of England.] 



III. LUDWIGIA. LUDWIGIA. 



Marshy or almost aquatic herbs, with opposite leaves, and small 

 flowers solitary in the axils of the upper leaves. Limb of the calyx of 



4 short divisions. Petals very small, or, in the British species, none. 

 Stamens 4. Ovary and capsule 4-celled. Style distinct, with a capitate 

 stigma. Seeds numerous, without any tuft of hairs. 



The genus consists of a considerable number of species, widely 

 diffused over the hotter as well as the temperate regions of the globe, 

 in the New World as in the Old. In their general habit and small 

 flowers they resemble Peplis, and some other semi-aquatic Lythrariece, 

 but the inferior ovary and some other characters are entirely those of 

 Onagracece. 



1. L. palustris, Ell. (fig. 352). Marsh L. A small glabrous annual, 

 3 to 6 inches high or rarely more ; the lower part of the stem creeping 

 in mud or floating in water, branching and rooting at almost every 

 node. Leaves ovate and entire, 6 lines to an inch long. Flowers closely 

 sessile, with a small green calyx, no petals, very small stamens, and an 

 exceedingly short style, with a comparatively large capitate stigma. 

 The capsule rapidly enlarges, when ripe, about 2 lines long, obovate, 

 with 4 green angles, and numerous minute seeds. Isnardia palustrit, 

 Linn. 



