Aquatic Vascular Plants of New England: 



Part 4. Juncaginaceae, Scheuchzeriaceae, 



Butomaceae, Hydrocharitaceae 



by 

 G. E. Crowi and C. B. Hellquist2 



INTRODUCTION 



This is the fourth in a series of reports on the aquatic and wetland 

 flora of New England. These reports are being prepared to aid conser- 

 vationists, fish and game personnel, consultants, botanists and stu- 

 dents in the identification of aquatic plants. The coverage is strictly 

 New England but is of value throughout the northeast. Data have been 

 gathered from herbaria in New England and from personal field work. 



Chemical data presented represent samples from many waters 

 throughout New England. The alkalinity readings are total alkalinity, 

 expressed as milligrams per liter (mg/1) CaCOg. The number of obser- 

 vations are included in parentheses following alkalinity and pH 

 values. Since pH and alkalinity vary greatly during the day, the values 

 are only indicative of the water quality. Chloride values are given 

 where data are available and of value. 



The rare and endangered plants lists referred to are those prepared 

 for each of the six New England states by the New England Botanical 

 Club in cooperation with the United States Fish and Wildlife Service, 

 Office of Endangered Species, Newton Corner, MA (RI — Church and 

 Champlin, 1978; MA — Coddington and Field, 1978; VT — Country- 

 man, 1978; ME — Eastman, 1978; CT — Mehrhoff, 1978; NH — Storks 

 and Crow, 1978). Taxa indicated as rare, threatened or endangered for 

 the entire New England Region are also noted (Crow et al., 1981, Rho- 

 dora 83: 259-299). 



We invite comments and/or criticisms on this treatment. Informa- 

 tion on any species omitted or any known localities not documented by 

 us will be welcomed. If anyone is interested in specific localities of any 

 of the species indicated on the dot maps, please contact us. 



Dr. G. E. Crow, Department of Botany and Plant Pathology, Nesmith Hall, Univer- 

 sity of New Hampshire, Durham, NH 03824. 



Dr. C. B. Hellquist, Department of Biology, Boston State College, 625 Huntington 

 Avenue, Boston, MA 02115. 



