15 



2. Elodea canadensis Michx. Fig. 7, Map 9 



Generally common in alkaline lakes, ponds and streams of New 

 England. Staminate plants are rarely encountered and have leaves 

 which tend to be longer and more linear or lance-oblong than the pistil- 

 late plants. Range extends from Quebec west to Saskatchewan and 

 Washington, south to North Carolina, Alabama, Iowa, Texas, New 

 Mexico, Arizona, and California. 



Rare and endangered plant list: New Hampshire 



alkalinity: mean 67.7 mg/1; range 10.0-153.0 mg/1; (64) 

 pH: mean 7.6; range 6.5-10.2; (60) 



Literature Cited and 

 Selected References 



Countryman, W. D. 1970. The history, spread and present distribution 

 of some immigrant aquatic weeds in New England. Hyacinth 

 Control J. 8: 50-52. 



Fernald, M. L. 1918. the diagnostic character of Vallisneria americana. 

 Rhodora20: 108-110. 



Hellquist, C. B. 1972. Range extensions of vascular aquatic plants in 

 New England. Rhodora 74: 131-141. 



Kausik, S. B. 1939. Pollination and its influence on the behavior of the 

 pistillate flower in Vallisneria spiralis. Amer. J. Bot. 26: 207-211. 



Knowlton, C. H. 1940. Two introduced plants. Rhodora 42: 524-525. 



Lawrence, D. K. 1976. Morphological variation in Elodea in western 

 Massachusetts: field and laboratory studies. Rhodora 78: 739-749. 



Marie- Victorin, F. 1931. L'Anacharis canadensis. Histoire et solution 

 d'un imbroglio taxonomique. Contr. Lab. Bot. Univ. Montreal 18: 

 1-43. 



Marie- Victorin, F. 1943. Les Vallisneries americaines. Contr. Inst. Bot. 

 Univ. Montreal 46: 1-38. 



St. John, H. 1920. The genus Elodea in New England. Rhodora 22: 17-29. 



St. John, H. 1965. Monograph of the genus Elodea: part 4. Summary. 

 Rhodora 67: 1-35; 155-180. 



Thieret, J. W. 1971. Observations on some aquatic plants in northwest- 

 ern Minnesota. Mich. Bot. 10: 117-124. 



Wylie, R. B. 1913. A long-stalked Elodea flower. Bull. Lab. Nat. Hist. 

 State Univ. Iowa 6: 43-52. 



Wylie, R. B. 1917. The pollination of Vallisneria spiralis. Bot. Gaz. 

 (Crawfordsville) 63: 135-145. 



