ZOSTERACEAE. 13 



1. N. flexilis (Willd.) R. & S. Stem slender, forking; leaves 

 linear, pellucid, acuminate or acute, 1-2 cm. long, 1-2 mm. wide, 

 numerous and crowded on the upper branches with 25-30 minute 

 teeth on each margin; fruit 2-4 mm. long, 0.5-1 mm. in diameter; 

 style long, persistent; stigmas short. 



Near Soldiers' Home, Hasse, Davidson. 



Family 6. ZOSTERACEAE. Eel-grass Family. 



Submerged marine plants with creeping rootstocks, 

 flattened branching stems and sheathing 2-ranked 

 ribbon-like leaves. Flowers monoecious or dioecious, 

 arranged on a one-sided spadix enclosed in a spathe. 

 Perianth none, but flowers enclosed by a hyaline scale. 

 Staminate flowers a single sessile anther arranged in 

 two rows on the spadix; pollen of slender filaments. 

 Pistillate flower of a single 1-celled ovary, with 2 carpels 

 and 2 slender stigmas. 



Flowers monoecious; ovary and fruit ovoid. 1. Zostera. 



Flowers dioecious; ovary and fruit heart-shaped. 2. Ph\'llospadix. 



1. ZOSTERA L. Eel-grass. 



Marine plants, wholly submerged, with slender root- 

 stocks and branching compressed stems. Leaves 2- 

 ranked, sheathing at the base, the sheaths with inflexed 

 margins. Spadix linear, contained in a spathe. Flowers 

 monoecious, arranged alternately in 2 rows on the 

 spadix. Staminate flower merely an anther attached to 

 the spadix near its apex, 1-celled; pollen thread-like. 

 Pistillate flower fixed on its back near the middle. 

 Ovary 1; style elongated; stigmas capillary. Mature 

 carpels flask-shaped, beaked by the persistent style. 

 Seeds ribbed; embryo ellipsoidal. 



1. Z. marina L. Leaves ribbon-like, obtuse at the apex, 0.5-2 

 m. long, 5-10 mm. wide; spadix 2-5 cm. long; flowers about 6 mm. 

 long, crowded. 



Shoal waters in bays on muddy bottoms. San Pedro. 



2. PHYLLOSPADIX Hook. 



Submerged marine plants with thickened rootstocks 

 and slender stems, which bear the inflorescence at the 



