4 MONANDRIA— MONOGYNIA. Zostera. 



Nat. Ord. Inundatce. Linn. 15. Naiades. Juss. 6. Akin 

 to Halorageac. Br. Terr. Austr. 17. Very doubtful. 

 " Most akin to Myriophyllum, and Callitriche." Br. 



Cat. a border, scarcely discernible, crowning the oval germen. 

 Cor. none. Filam. superior, produced as the anther 

 ripens. Anth. of 2 round lobes ; at first sessile. Style 

 awl-shaped. Stigma simple, acute. Seed oval. 



Aquatic herbs. Stem simple, hollow. Leaves whorled. Fl. 

 axillary, sessile, naked. 



1. H. vulgaris. Common Mare's-tail. 

 Leaves linear, many in each whorl. 



H. vulgaris. Linn. Sp. PL 6. Willd.v. 1 . 26. VahlEnum. v. 1. 13. 



Fl. Br. 4. Engl. Bot. v. 1 1 . t. 763. Curt. Lond. fasc. 4.t.\. 



Hook. Scot. 2. Fl. Dan. t. 87. Bull. Fr. t. 365. Poit. et Turp. 



Par. l.t.l. 

 Limnopeuce. Rail Syn. 136. 

 L. n. 1572. Hall. Hist. v. 2. 264. 

 Cauda equina foemina. Ger. Em. 1 114./. 

 Polygonum foemina. Camer. Epit. 689./. 

 Equisetum palustre, linariae scopariae folio. Bauh. Pin. 15. Prodr. 



24. Dill, in Raii Syn. 136. 



In ditches, pools, and the borders of slow streams. 



Perennial. May, June. 



Root creeping. Stem a foot, or more, above the water, round, 

 juicy, polished, reddish, with many whorls of spreading, linear, 

 entire, smooth, single-ribbed leaves. Fl. small. Anth. red be- 

 fore it bursts. 



The lower leaves, deep under water, are long, thick-set, pellucid, 

 and pale ; the herb in winter bearing no other. In this state it 

 is noticed by Dillenius as a remarkable variety. 



3. ZOSTERA. Grass-wrack. 



Linn. Gen. 472. Juss. 24. Fl. Br. 7. Sm.in Rees's Cycl. v. 39. Lam. 



t.737. Gcertn.t.\9. 

 Nat. Ord. Piperita?. Linn. 2. Aroideee. Juss. 7. Fluviales 



of Richard. Hook. Scot. 192. 



Cat. none, except an oblong sheath, formed of the base of 

 the leaf, splitting lengthwise. Cor. none. Spadix linear, 

 covered in front with many naked flowers. Anther cylin- 

 drical, tapering at each end, sessile, attached laterally, of 

 1 cell. Pollen mixed with branched fibres. Germen 

 shaped and attached like the anther, and parallel to it. 

 Style terminal, curved outwards, cylindrical. Stigm. 2, 



