277 



CXLIX. ZOSTERACEiE. 

 1. ZOSTERA, Linn. 



1. Z Marina, Linn. sp. 1374. — A salt-water plant, submersed ; 

 stems slender ; leaves scattered, narrow-linear acute, 5-nerved ; 

 floral leaves shorter, swelled out above the base into a sheathing 

 spathe ; stipules united into a sheath, elongated and membranace- 

 ous ; spadix the length of the spathe ; fruit obliquely oblong, acu- 

 minated and beaked at the apex; seed cylindric oblong. In the 

 Saltpans near Malwan. 



CL. NAIADACE^. 



1. NAJAS, Willd. 



1. N Indica, Chamisso in Linn, iv, 501. — An aquatic, stem 

 round dichotomous ; leaves tern or opposite, elongated, very 

 narrow-linear, remotely denticulate; sheath dentate, ciliate ; ovaries 

 axillary solitary, sessile; style bifid. Common in tanks. Syn. 

 Caulinia indica, Willd. in"Aet. Acad. Berol. 1798, 89, t. 1, /. "3 ; 

 Fluvialis indica, Pers. Syn. ii, 680 ; N dichotoma, Roxb, Fl. 

 Ind. iii, 749(?). 



CLI. HYDROCHARIDACE^. 



1. HYDRILLA, Richard. 



1. H Veeticillata. — An aquatic, with long slender stems; 

 leaves small, verticelled, sessile, oblong serrulate ; male flowers 

 minute, axillary sessile ; calyx spathaceous murexed ; perianth 

 3-leaved ; anthers 3 ; female flowers on a different plant, axillary, 

 solitary; spathe sessile, tubular; tube of the periantli filiform 

 elongated, connate, with the ovary ; the limb 6-divided ; ovary 1 

 celled, with 3-parietal placentae. Common in tanks. Syn. Serpi- 

 cula verticillata, Roxb. Fl. Ind. iii, 578. 



2. NECHAMANDRA, Planch. 



1. N RoxBUHGHii, PI. Ann. Soc. Nat. (ser. iii.) xi, p 79. — 

 Aquatic submersed ; leaves alternate, grassy, stem-clasping, acute, 

 many-nerved, minutely serrulated, pellucid ; flowers dioecious ; male 

 spathe ovate, enclosing many flowers, thickly clustered on a conical 

 spadix, and leaving it at the time of flowering ; perianth of 6 

 divisions ; stamens 2 ; female spathe tubular, bifid at the apex ; 

 tube of the perianth attenuated upwards, crowned with the 3-parted 

 limb; stigmas 3; ovary ovate-lanceolate, 1 -celled; ovules parietal. 



