Fig. 75B: Thalassia testmUnum: a, staminate flower, enlarged; b, pistillate flower 

 enlarged. (Courtesy of R. K. Godfrey). 



In fresh or rarely brackish water, commonly in still water of streams, in Okla. 

 (Alfalfa, Delaware, Ottawa and Sequoyah cos.) and N. M. (Taos Co.), May-Oct.; 

 Que. to N. C, westw. to Minn., Okla. and N. M.; also Ida. 



5. Thalassia Sol.^nd. 



Turtle-grass 



Several species in marine waters of tropical and warm temperate regions. 



1. Thalassia testuduium Konig, Palmas del mar. Figs. 75A and 75B. 



Submersed perennial herb with thick creeping scaly rhizome 3-5 mm. thick, 

 dioecious; the short stems covered by the fibrous remains of old leaves; leaves 

 several, 2-ranked, clustered on short erect branches, sheathing at base, linear, 

 to 35 cm. long and 1 cm. wide, glabrous, minutely serrulate at the obtuse- 

 rounded apex, withering-persistent; scapes arising from the leaf axils, bearing a 

 solitary unisexual flower in a 2-cleft tubular spathe whose lobes are elliptic and 

 papillose-dentate on the margins; staminate flowers pedicelled; pistillate flower 

 nearly sessile in the spathe; perianth lobes 6, in both kinds of flowers oblong, 

 rounded above, 1-1.2 cm. long; stamens 9; anthers about 8 mm. long, linear, 

 opening laterally; stigmas 9 to 12, linear-filiform, pilose, grooved on the inside, 

 about 1 cm. long; fruit oval to ellipsoid-fusiform, short-stalked and short-beaked, 

 densely warty-mammillate, opening by valves, 2 cm. or more long. 



In shallow salt water along the Gulf Coast where it forms dense and extensive 

 marine meadows in bays and about reefs, occasional in beach drift; from Fla. to 

 Tex., s. to n. S. A. 



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