North American Cyperacete. 32d 



the western parts of the State of New York, Dr. Gray ! ; on 

 the Missouri above St. Louis, Dr. Baldwin! 



y. ajlindricus. Spikes cylindrical-oblong, somewhat acute ; 

 scales ovate, somewhat pubescent, aristately mucronate 5 bristles 

 about 4, rigid, nearly as long as the nut ; style 3-cleft ; nut 

 obovate, abruptly acuminate, narrowed below, obtusely angular 

 in front, flat on the back, smooth. 



Culm and umhel as in the preceding variety. Spikes an inch long, 

 and only one-third of an inch in diameter. 



Hab. Georgia, Dr. Baldwin! 



Obs. The variety /3. differs so much from the common S. 

 maritimus of our salt marshes in the appearance of the ripe spike 

 and in the form of the nut, as well as in the length of the brisdes, 

 that I should have proposed it as a distinct species, did not the 

 succeeding variety connect the two, and seem to show that they 

 are all forms of one species. Which of the three is the S. 

 maritimus of Europe I am unable to say, as my foreign speci- 

 mens are not sufficiently mature to exhibit the ripe fruit. The 

 first variety seems by its lenticular smooth nut, to be exactly 

 S. maritimus of N. ab Esenb. (1. c.) ; but Roemer and Schultes, 

 in their detailed description of the same species, state that 

 the nut is triquetrous, and the bristles equalling it in length. 

 Smith, (in Eng.jl. 1. p. 61) describes the nut as " roundish, 

 shining brown, with 3 blunt angles, and from one to five or six 

 rough bristles." Perhaps both varieties occur in Europe, as 

 they do in this country; the one being confined to the neigh- 

 bourhood of salt water, and the other inhabiting the borders of 

 fresh water rivers and lakes. 



9. SCIRPUS ATROVIRENS, Mukl. 



Culm triangular, leafy; umbel compound, proliferous; invo- 

 lucre about 3-leaved ; spikes ovate, acute, glomerated in dense 

 heads of 15 — 20; scales ovate, mucronate, pubescent; bristles 

 as long as the nut ; style 3-cleft ; nut obovate, minute, com- 

 pressed-triangular, tapering towards the base, acuminate, dull. 



