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Morong, T, 1893. The Najadaceae of North America. Mem. 

 Torrey Bot. Club 3: 1-65. 



Ogden, E. C. 1943. The broad-leaved species of Potamogeton of 

 North America north of Mexico. Rhodora 45: 57-105, 

 119-163, 171-214. 



Ogden, E. C. 1974. Potamogeton in New York. Bull. No. 423. 

 New York State Museum and Science Service. Albany, New 

 York. 20 pp. 



Reznicek, A. A. and R. S. W. Bobbette. 1976. The taxonomy of 

 Potamogeton subsection Hybr idi in North America. Rhodora 

 78: 650-673. 



St. John, H. 1916. A revision of the North American species of 

 Potamogeton of the section Coleophylli Rhodora 18: 121-138. 



Stuckey, R. L. 1979. Distributional history of Potamogeton 

 cr ispus (Curly Pondweed) in North America. Bartonia 

 46: 22-42. 



Ru ppia (Widgeon-grass) 



Submersed plants of saline water arising from rhizomes; 



leaves alternate, blades fused with the stipule; floating 



leaves absent; flowers 2, enclosed in leaf sheath at anthesis, 



fruits long-stalked, 4 per flower, usually below the water 

 surface . 



1. Ru ppia mar itima L. Fig. 37, Map 37 



Common in brackish and saline water along the coast. 

 Richardson (pers. comm.) has observed that peduncles of 

 underwater pollinated flowers remain straight, while peduncles 

 of surface pollinated flowers become recoiled following 

 fertilization. This treatment includes the seven varieties 

 recognized by Fernald (1950). Richardson (in press) notes that 

 R. mar itima is a plant of broad ecological amplitude and that 

 clinal variations in vegetative morphology and reproductive 

 behavior observed in New Hampshire salt marshes are apparently 

 expressions of adaptation to a diversity of habitats. It 

 appears to us that a re-evaluation of the varieties is 

 necessary. Range extends along the coast from Newfoundland to 

 Florida and along the Pacific Coast from Washington to 

 California and Mexico; at scattered locations inland. 



alkalinity: mean 42.7 mg/1; range 7.0-169.0 mg/1 



pH : mean 7.9; range 6.4-10.7 



chloride: mean 1729.3 mg/1; range 191.1-4095.0 mg/1 



