MARE'S-TAIL TRIBE 95 



3. ISNARDIA 



I. 7. palustris (Marsh Isnardia). — The only British species. A 

 small, herbaceous plant, 6-8 inches long, with prostrate rooting 

 stems ; leaves ovate, smooth, stalked, and opposite ; and small 

 axillary sessile fioiecrs, which are destitute of petals. Very rare. 

 Has been found only at Buxstead in Sussex, and in the New Forest. 

 — Fl. July. Annual. 



4. CiRC.EA [Enchanter's Nightshade) 



1. C lutetiana (Common Enchanter's Nightshade). — A slender, 

 herbaceous plant 1-2 feet high, with a branched, downy stem ; egg- 

 shaped leaves, toothed and pointed, and hairy calyx. The roots are 

 creeping, the flowers small, white, with pink stamens, and are borne 

 in graceful branched racemes, and are succeeded by 2-lobed, hairy 

 seed-vessels. Damp shady places ; common ; often a troublesome 

 weed in damp gardens. — Fl. July, August. Perennial. 



2. C. Alpina (Alpine Enchanter's Nightshade). — Stem nearly 

 smooth ; leaves heart-shaped, toothed, shining. Closely resembling 

 the last, but smaller and less branched ; 5-R inches high ; the frttit 

 is not so bristly, and is usually i-seeded. The leaves are remark- 

 able for their delicate textiue, and when dried are nearly frans- 

 parent. Mountainous woods in the north. — IT. July, August. 

 Perennial. 



Natural Order XXVI 



HATORAGACE^.— The Mare's-tail Tribe 



Calyx adhering to the ovary, and either expanding into 3 or 4 

 minute lobes, or reduced to a mere rim ; -petals either minute and 

 placed on the mouth of the calyx, or wanting ; stamens either 

 equalling the petals in number, twice as many, or, when petals are 

 absent, I or 2 ; ovary with one or more cells ; stigmas equal in 

 number to the cells of the ovary ; capsule not opening ; seeds 

 solitary, pendulous. An unimportant Order, comprising about 

 eighty .species of plants, scattered over most jiarts of the globe, 

 none of which have any economic use. Th^y are for the most part 

 herbaceous aquatics, with inconspicuous flowers often destitute of 

 petals, and in one genus, Hippuris (Mare's-tail), composed of a 

 minute calyx, a solitary stamen, and a single seed. In several 

 species the stamens and pistils are in separate flowers. 



I. Hippuris (Mare's-tail). — Calyx forming a minute, indistinctly 

 2-lobed rim for the ovary ; petals ; stamen i ; style i ; seed i ; 



