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Yale University Herbarium

YU.028412

PLANTAE EXSICCATAE GRAYANAE

410. Potamogeton pusillus L.,
Var. typicus FERN.

Mem. Am. Acad. xvii. no. 1, 81, pls. 16; 30, fig. 6; 35, fig. 1 (1932).

Syn. *P. pusillus* L. Sp. Pl. 127 (1753). *P. pusillus* var. *vulgaris* Fries, Nov. Fl. Suec. ed. 2, 49 (1828); Tuckerm. Am. Journ. Sci. ser. 2, vii. 355 (1849); Graebn. in Engl. Pflanzenr. iv. fam. 11, Heft 31, 115, fig. 27 J, K (1907). *Spirillus pusillus* (L.) Nieuwl. Am. Midl. Nat. iii. 18 (1913).

Very brittle rigid form with winter buds; fresh plant atroviridous.

Flowering in 1 m. of water in quiet muddy backset in
Charles River, Dedham, Massachusetts.

Coll. M. L. FERNALD, H. K. SVENSON.

July 24, 1928