202 Rhodora [NovEMBER 
submerged at high tide. In its leaves and involucre the plant might 
pass as a dwarf halophytic variant of B. comosa, but it has conspicu- 
ously striate 4-awned achenes more suggestive of those of B. cernua. 
From dwarf forms of the latter species, however, it is clearly distinct 
in its petioled or merely sessile entire or remotely dentate leaves, its 
ellipsoid-campanulate heads, the few (2-4) very long ascending 
foliaceous bracts, and the flattish, not 4-angled, achene. The writer, 
after studying the descriptions of recently proposed species of Bidens, 
could find only one description, that of B. hyperborea Greene from 
Rupert House, James Bay, which closely approached the Gaspé 
plant. In many points Professor Greene’s diagnosis scarcely fitted 
the more eastern plant, so that the writer applied to Professor John 
Macoun for an opportunity to examine the type of B. hyperborea which 
is in the Herbarium of the Geological Survey Department at Ottawa. 
This original material which Professor Macoun generously loaned the 
writer is a sheet of three small plants which, as stated by Professor 
Greene, are quite simple and monocephalous, thus differing from the 
Gaspé material which is usually freely branched with very numerous 
heads. ‘The Rupert House plants, furthermore, have shorter outer 
bracts than most of the Gaspé specimens. Except for these discrepan- 
cies the two plants are essentially alike,— in their foliage, corollas, 
chaff, and achenes identical. The more abundant collections from 
eastern Quebec add much to our knowledge of the plant, however, 
and that it may be more readily recognized by others who find it the 
following description, somewhat amplifying the original account of 
the species, is given. 
BIDENS HYPERBOREA Greene, Pittonia, iv. 257 (1901). Stems 
5-25 cm. high, simple, or more often slightly to freely branched, 
erect or depressed and matted, glabrous: leaves rather fleshy, nar- 
rowly spatulate to oblanceolate, 1.5-6.5 cm. long, 3-9 mm. broad, 
entire or remotely 2—4-dentate, obtuse at tip, narrowed to a sessile 
or short-petioled base: heads ellipsoid-campanulate, the involucre 
5-10 mm. in diameter; outer bracts 2-4, strongly ascending, foliace- 
ous, 2-6 сш. long: inner bracts 8-12, narrowly oblong, obtuse or 
subacute, yellow, with dark striations: chaff similar, about equaling 
the awns: ligules (when developed) narrowly obovate to oblong, 4-6 
mm. long, deep yellow: disk-corollas funnelform, about equaling the 
awns; the 4 short ascending blunt teeth exceeding the purple anthers: 
achenes linear-cuneiform, 7 mm. long, 1.8 mm. broad at the rounded 
summit, flattish, about 15-ribbed on each face; the midrib scarcely 
thickened; the margins (and sometimes the midribs) retrorsely barbed: 
