The Botany of Iceland - 01.12.1942, Page 101

THE PTERIDOPHYTA AND SPERMATOPHYTA OF ICELAND
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Isoetaceae.
14. Isoetes echinospora Dur., Bull. soc. bot. de France VIII (1861)
p. 164.
Babington, 1871, p. 346.—Gronlund, Isl. Fl., 1881, p. 136.—Stefánsson, Fl. ísl.
ed. 1, 1901, p. 14.—Ibid. ed. 2, 1924, p. 15,—C.H.O., Fl. arct., 1902, p. 15 —
O. & Gr., 1934, p. 2.
Fl. Dan. tab. 2743.
Icelandic: Álftalaukur. Danish: Gulgron Brasenfode. English: Quillwort.
This species was for the first time collected by J. Steenstrup in Laugarvatn, S.—
From the rather numerous localities recorded later on it would seem that it may
be common in S.W., and it is likely that it is rather frequent in other parts
also. See fig. 17. Cp. also H.J. in „Skýrsla”, 1909, p. 31 and 1913, p. 30.—
H.J. found I. echinosþora growing abundantly in Laugarvatn in 1911 (H.J., 1913,
loc. cit.).
Life-form: HH. (Hydrophyte).
On the bottom of lakes and pools, in shallow water.
Max. length of leaves: 10 cm; average: 5 cm.
Geogr. area: Northern North America, southward to Pennsylvania and California
(I. Braunii Engelmann).—Greenl.: W. 60°—61°35'. E. 60°.—Eur.: Fær.; E.S.I.;
northern Scandinavia and Russia to central France.—Northeastern Asia: Kamchatka
to Honshu.
15. Isoetes lacustris Linn., Sp. pl. ed. I (1753) p. 1100.
Hooker in Mackenzie, 1811, p. 428.—Babington, 1871, p. 346.—O. & Gr.,
1934, p. 2.—Ingimar Óskarsson, 1937, p. 40.—St. Steindórsson, 1937, p. 36.
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