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34
THE MARINE ALGÆ OF NEW ENGLAND.
Wood’s Holl, Mass.; Atlantic shore of Europe. Summer
A species easily recognized and probably common along the New England coast in summer, but rarely
found in sufficient quantities to make herbarium specimens. It is usually found in small streaks, so
entangled with other Nostochineæ and Confervæ as to be quite inextricable. At times it is found
tolerably pure on the old stalks of Spartina, between tide-marks. Pure specimens may be obtained by
allowing specimens in which filaments of this species are entangled to remain overnight in a shallow
dish of salt water, when the Microcoleus will have freed itself from other substances and come to the
surface. As generally found, the plant looks like an attenuated cornucopia, owing to the rupture of the
sheath in the middle, allowing the filaments to project. This is shown in Harvey’s figure, l. c., and also
in Pl. II, Fig. 3, where only half of the plant has been drawn. Normally the sheaths are about a quarter
of an inch long, about .075 mm broad in the middle, and tapering to about .012 mm at the ends. Color a
deep bluish green. The filaments readily escape from their sheath, and might in this condition pass for
a species of Oscillaria.
MICROCOLEUS TERRESTRIS, Desmaz. (Chthonoblastus repens, Kütz.), and M. VERSICOLOR, Thuret, are not
infrequently found in muddy places in the interior of New England.
LYNGBYA, Ag.
(Named in honor of Hans Christian Lyngbye, a Danish botanist.)
Filaments free, each provided with a distinct sheath, simple, destitute of
heterocysts, no proper oscillations. Spores unknown.
L. MAJUSCULA, Harv.; Mermaid’s Hair. (Conferva majuscula, Dillw.—L. crispa, Ag.
in part,—L. majuscula, Harv., Phyc. Brit., Pl. 62; Ner. Am. Bor., Part III, p. 110, Pl.
47 a.) Pl. I, Fig. 4
Filaments Long, forming floating tufts, crisped, about .028 mm to .032 mm in diameter,
blackish green, sheath prominent, cells 8 to 10 times as broad as long.
Cape Cod, Mass., to Key West; Europe; Pacific Ocean. Common and widely diffused.
Summer.
The largest, most striking, and most common of our marine Lyngbyæ, easily recognized by the length
and diameter of its filaments and its color, which is a blackish green. It forms during the later summer
months large tufts upon Zostera and various other algæ, and is often found floating free in considerable
quantities. In the center of the masses the filaments are intricately twisted together, but on the surface
they float out from one another, so as to deserve the common name of mermaid’s hair. In the older
specimens the filaments are very much curled and twisted, forming the L. crispa of some writers. The
sheath is always well marked, although, as is the case in all the species, it varies so much in thickness
under different circumstances as to render it impossible to give accurate measurements. The
heterocysts, “cellulis interstitialibus sparsis,” described by Rabenhorst in this species, Flora Europ.
Alg., Part II, p. 142, have, in reality, no existence.
L. ÆSTUARII, Liebm. (L. æruginosa, Ag.—L. ferruginea, Ag., in Ner. Am. Bor. Part
III, p. 102, Pl. 47 b; Phyc. Brit., Pl. 311.)
Filaments forming a verdigris-green stratum, about .016-18 mm in diameter, sheaths
distinct.