The Botany of Iceland - 01.12.1942, Síða 127

THE PTERIDOPHYTA AND SPERMATOPHYTA OF ICELAND
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Rare, but very likely overlooked in several places. In Hornafjörður it was present
rather abundantly in some places (I.Ó., 1937a, p. 41). See fig. 39.
Life-form : HH (Hydrophyte).
In lakes and ponds, and in not too warm springs.
Flor. VI—VIII. fr. mat. VII—VIII.
Max. length : 27 cm ; average : 20 cm.
Geogr. area: (widely distributed throughout the world, save for the polar countries).
—Am. : Nearly throughout N. Am. except in the extreme north.—Eur.: E.S.I. :
throughout Eur.—Asia.
Fig. 39. .Jattnzc/iW/m þalustris L.—Double-ring: Rupþia maritima L.
45. ^ostera marina Linn., Sp. pl. ed. I (1753) p. 968.
Babington,- 1871, p. 335.—Gronlund, Isl. Fl., 1881, p. 106.—Z- marina L. var.
stenophylla A. & Gr., Stefánsson, Fl. Isl., ed. 1, 1901, p. 20.—Ibid., ed. 2,
1924, p. 22.—Z■ marina L., C.H.O., Fl. arct., 1902, p. 18,—£. marina L.
var. stenoþhylla Asch. & Gr., O. & Gr., 1934, p. 14.
Icon. : Reichenbach, Ic. fl. German. VII, t. III, fig. 3 (Z- angustifolia Rchb.).
Icelandic: Marhálmur. Danish : Bændeltang, Aalegræs. English : Grass-wrack.
Most, if not all, of the material collected at the coasts of Iceland seems to belong
to the var. stenoþhylla Aschers. & Graebn., the leaves being usually only from
L5 to 2.5 mm broad; more rarely fully 3 mm broad. From Stykkishólmur and
Skerjafjörður, in W. Icel., H.H. contains specimens with fully ripe fruits.
Here and there along the coast; on the south coast from Hornafjörður, westward
as far as to Reykjavík it has not yet been observed. Along the coasts of Breiðifjörður
and Faxafjörður it is fairly common, cp. Á. Friðriksson in Náttúrufræðnigurinn VI,
1936, p. 47 See fig 4Q
Life-form: HH (Hydrophyte).