The Botany of Iceland - 01.12.1942, Page 190

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JOHS. GRONTVED
Juncus balticus X J- filiformis.
Helgi Jónsson, 1899, p. 186.—Stefánsson, Fl. ísl., ed. 1, 1901, p. 23.—Ibid., ed. 2,
1924, p. 25.—Steindórsson, 1933, p. 36.—I. Óskarsson, 1932, p. 21.
Specimens with intermediate characters between J. balticus and J. filiformis
have been taken in several places and many records have also been made from places
where the parent plants are growing; the hybrid does not seem altogether rare. In
some specimens kept in H.H., the capsules are fairly well developed but the seeds
are obsolete, thus indicating the hybrid nature of the plants.
137. Juncus biglumis Linn., Sp. pl. ed. I (1753) p. 328.
K. & M., 1770, p. 206.—Babington, 1871, p. 332,—Gronlund, Isl. Fl., 1881,
p. 102.—Stefánsson, Fl. Isl., ed. 1, 1901, p. 24.—Ibid., ed. 2, 1924, p. 26.—
C.H.O., Fl. arct., 1902, p. 25,—O. & Gr., 1934, p. 43.
Flora Dan. tab. 120.
Icelandic: Flagasef. Danish: Toblomstret Siv. English: Two-flowered Rush.
Rather common in most parts of the lowland except in S. where it seems to be
somewhat rare. Common in the central parts.
Life-form: H.
In clayey and gravelly wet places; on bare moist soil (flag), in bogs and moors.
Flor. VI—VII; fr. mat. VII—VIII.
Max. height: 18 cm ; average : 9 cm.
Geogr. area: Am.: Ellesmere Land and Labrador to Alaska, southward to Brit.
Columbia.—Greenl. : Circumgreenlandic.—Eur.: Fær.; S.; central Scandinavia and
N. Russia, Spitsbergen, Novaya Zemlya; Alps.—Asia: N. Siberia, southward to
Yakutsk and E. Altai, Kamchatka.
138. Juncus bufonius Linn., Sp. pl. ed. I (1753) p. 328.
K. & M., 1770, p. 206.—Babington, 1871, p. 333.—Gronlund, Isl. Fl., 1881,
p. 101.—Stefánsson, Fl. ísl., ed. 1, 1901, p. 25.—Ibid., ed. 2, 1924, p. 28.—
C.H.O., Fl. arct., 1902, p. 26,—O. & Gr., 1934, p. 42.
Flora Dan. tab. 1098.
Icelandic: Lindasef. Danish: Tudse-Siv. English: Toad-Rush, Frog-grass.
Most of the Icelandic specimens seem to belong to f. ranarius (Song. & Perr.)
= J. ranarius Song. & Perr., with the petals shorter than the sepals, and as long
as the capsule or a little longer, but the characters are not altogether marked in
the Icelandic specimens. When growing near hot springs the specimens are usually
low and dwarfish : f. pygmaeus.
In S., S.W., N. and E. common; in N.W. and S.E. rare. In the central parts
it is found only near the hot springs at Hveravellir (J.Gr., 1934; V.R., 1935);
Hattver (S.S., 1931).
Life-form: Th.
On moist soil; in strand meadows, on moist, clayey flats; on the banks of brooks,
near warm springs.
Flor. VI—VIII; fr. mat. VII—IX.
Max. height: 20 cm ; average : 9 cm.
Geogr. area: Am. : Throughout N. Am.—Greenl.: W. 60°43'—60°59' & 66°55'
and 67°49'.—Eur. : Fær.; E.S.I.; throughout Eur.