60 ENGLISH BOTANY. 



Walton-on-tlie-Naze, Essex, where I gathered both forms growing 

 togctlier in the beginning of September, R. spiraUs was in full flower, 

 and had none but very young fruit, while R. rostellata had some of 

 the fruit quite ripe. 



Lesser Ruppia. 



German, SchnahelfriicMige Riippie. 



GENUS I r.— Z O S T E R A. Linn. 



Flowers numerous, monoecious, sessile, disposed in two rows on the 

 face of a flattened membranous spadix which is spht longitudmally on 

 the inner fice, and terminates in a foliaceous point or lamina. Perianth 

 none. Male flowers consistin"; of a single subsessile 1-celled anther. 

 Female flowers reduced to a 1-celled and 1-ovuled solitary carpel; 

 style persistent; stigmas 2. Fruit a membranous utricle bursting 

 transversely. 



Submerged herbs growing in the sea below or near low water mark, 

 with long ribbon-like dark green parallel-veined leaves. 



The name of tliis genus of plants is taken from the Greek word ^wori/p a ribbon 

 or girdle, which the leaves slightly resemble. 



SPECIES I.-Z OS TERA MARINA. Linn. 

 Plates MCCCCXXIX. MCCCCXXX. 



Leaves broadly linear or linear, Avith 1 to 5 strong ribs, and very nume- 

 rous slender ones between them. Pedimcle of the spathe thickened 

 upwards and compressed, shorter than the spadix. Spadix strap- 

 shaped, without marginal bands, many-flowered. Spathe gradually 

 enlarged above the peduncle, with a long foliaceous point. Nuts 

 oblong-ovoid, longitudinally striate. 



Var. a, genuina. 

 Plate MCCCCXXIX. 



BeicJi. Ic. n. Germ, et Helv. Vol. VU. Tab. IV. Fig. 4. 



Z. marina, Reich. 1. c. p. 3. Hartm. Skand. Fl. ed. ix. p. 216. 



Leaves broadly linear, 3 to 7 ribbed. 



Var. 3, anrjustifolia. Fries. 



Plate MCCCCXXX. 



Beich Ic. Fl. Germ, et Helv. Vol. VII. Tab. HI. Fig. 3. 



Ti. angustifolia, Eeich. 1. c. p. 3. Ilarlm. Skand. Fl. ed. ix. p. 217. 



Leaves narrowly linear, 1- to 3-ribbed. Peduncles longer in pro- 

 portion to the spadix than in var. a, and the whole plant smaller. 



