94 



ZOSTERACEAE 



1. Zostera marina L. 



Eel-grass. 



Fig. 198. 



Zostera marina L. Sp. PI. 968. 1753. 



Zostera marina latifolia Morong, Bull. Torrey Club 13: 



160. 1886. 

 Zostera pacifica S. Wats. Proc. Am. Acad. 26: 131. 1891. 

 Zostera orcgona S. Wats. Proc. Am. Acad. 26: 131. 



1891. 

 Zostera latifolia Morong, Mem. Torrey Club 3=: 63. 1893. 



Stems branched, 1-3 m. long, from a thick 

 rootstock. Leaves ribbon-like, obtuse at the apex, 

 3-15 dm. long, 2-8 mm. wide, with 2-7 principal 

 nerves; spadix 25-60 mm. long; flowers crowded, 

 usually 10-20 of each kind on the spadix, 6 mm. 

 long ; the anthers at anthesis escape from the spathe 

 and discharge the glutinous filamentous pollen into 

 the water ; ovary somewhat vermiform ; the 

 stigmas at anthesis protrude through the spathe 

 and drop off before the anthers of the same 

 spadix open, the ribs showing clearh- through the 

 pericarp, seed strongly 20-ribbed, about 3 mm. 

 long and 1 mm. in diameter, truncate at both ends. 



In bays and estuaries, usually growing on muddy bottoms; widely distributed in the Atlantic and Pacific 

 Oceans. The common form of the Pacific Coast has broad leaves, 6-12 mm. wide, the broadest with 10-13 

 principal nerves. Type locality: Europe. 



2. PHYLLOSPADIX Hook. Fl. F.or. Am. 2 : 171. 1838. 



Submerged marine plants with thickened rootstocks and slender stems, which bear the in- 

 florescence at the summit or in clusters along the upper part. Leaves linear, sheathing. 

 Flowers dioecious in spathes like those of Zostera. Spathes with membranous edges, the 

 back thickened and terminating in long leaf-like appendages. Spadix with a series of short 

 dilated foliaceous flaps, which close over the flower, spreading open at maturity. Staminate 

 flowers of numerous sessile stamens in 2 rows; anthers 1-celled. Pistillate of simple sessile 

 ovaries, attenuate into a short style ; stigmas 2, capillary. Fruit beaked by the short persistent 

 style, cordate-sagittate. [Greek, referring to the leaf-like appendages of the spathe.] 



Spadices several, cauline. 1- P- torreyi. 



Spadix usually solitary, basal. 2. P. scouleri. 



1. Phyllospadix torreyi S. Wats. 



Torrey 's Surf -grass. 



Fig. 



199. 



Phyllosfadix torreyi S. Wats. Proc. Am. Acad. 14: 303. 1879. 



Stems simple or branched, flat, Z-6 dm. long. Leaves 

 all submerged, linear, flat when young, becoming com- 

 plicate or terete, 2 m. long or less, 2 mm. wide or less, 

 primary nerves 1-3, or the leaves sometimes nerveless, 

 the base sheathing; spadices cauline, in 2 or 3 pairs, 

 usually about 5 cm. long, each pair subtended by several 

 fugacious bracts ; staminate flowers numerous, in 2 rows, 

 consisting of a single 1-celled anther; pistillate flowers 

 numerous, arranged in 2 rows ; fruit flask-shaped, 2-3 mm. 

 long, beaked by the persistent style, deeply cordate-sagit- 

 tate at the base, with 2 projecting wings, and sometimes 

 winged on the back. 



Growing among rocks in the surf at low tide mark to about 

 3 fathoms. Bolinas Bay, California, south to Ensenada, Lower 

 California. Type locality: .Santa Barbara. 



