Ealfs. Desm. (1848), p. 88, t. 14, f. 6. Archer in Prit. Inf.
(1861), p. 780, t, 1, f. 26. Wittrock Scan. Desm, (1869), p. 6.
Nordstedt Desm. Spitz. (1872), p. 37. Hassall Fr. Alg.
(1845), p. 383. Nordstedt Desm. Arct. (1875), p. 30, 41.
Brebisson Liste Desm. (1856), p. 124. Cleve Sver. Desm.
(1864), p. 485. Lundell Desm. Suec. (1871), p. 21.
Nordstedt Norges Desm. (1873), p. 10. Wolle Desm. U.S.
(1884), p . 106, t. 27, f. 8, 9.
Euastrum elegans, var. p. rostratum, Eabli. Alg. Eur. (1868),
p. 186. Kiroh. Alg. Schles. (1878), p. 159. Jacobsen Desm.
Denm. (1874), p. 191.
H ab. In pools.
Sussex, Westmoreland, Cornwall, Wales, Scotland; France,
Germany, Sweden, Norway, Russian Lapland, Spitzbergen,
Denmark, United States.
Plate X X X V ., fig. 2. a c e , living fronda ; 5 d f , empty fronda.
E uastzum e le g a n s . Preb. in Palfs. Desm. (1848), p. 89, i. 1 4 ,/. 7.
Frond minute, scarcely twice as long as broad, oblong ; segments
with their basal portion emarginate at the sides, connected
by a broad neck with the terminal portion; ends
protuberiint, rounded, acutely emarginate at the centre,
pouting ; side view with an inflation at the base of the segments,
sides concave, ends rounded. Zygospore ■ orbicular,
spiny.
Siz e . Diam. 18-86 g (W.) ; zygospore 25 g ; length
25-50 g ; diam. 17-35 g (R.)
Archer in Prit. Inf. (1861), p. 730. Nordstedt Desm. Arct.
(1875), p. 30. Cleve Sver. Desm. (1864), p. 485. Nordstedt
Noro-es Desm. (1873), p. 10. Petit Liste Desm. Paris (1877),
p 31 Wood P. Water Alg® U.S. (1872), p. 140. Brebisson
Liste Desm. (1856), p. 124. Rabh. Alg. Eur. (1868),
p. 186 in part. Wolle Desm. U.S. (1884), p. 106, t. 27, f. 10-
i ’G; f. 25-26. Wittrook Scan. Desm. (1869), p. 6. Wille
Nov. Sem. (1879), p. 32. Nordstedt Desm. Spitz. (1872), p.
37. ’ Jacobsen Desm. Denm. (1874), p. 191 (exol. rostrata).
Kirchner Alg. Sohles. (1878), p. 159 (partly).
Cosmarium elegans, Breb. in Meneg. Syn. Desm. (1840), p.
222
Euastrum hidentatuin. Nag. Ein. Alg. (1849), t. 7, f. D. 1.
H ab. In pools.
Widely distributed in England, Wales, Scotland; France,
Germany, Norway, Spitzbergen, Sweden, Nova Zembla, Denmark,
United States.
Plate X X X V ., fig. 3. a, living frond ; b, empty frond j c, zygospore.
II
var. a. Palfs. Pesm., p. 89.
Neck somewhat constricted, end portion bearing on each side
an acute horizontal spine-like projection.
Lundell Desm. Sueo. (1871), p. 22. Grunow Desm. Austr.
(1858), p. 501.
var. y. s p in o s um . Palfs. Pesm. (1848), p. 89, t. 14, f. 7 ,/.
Neck not constricted, lateral projections bearing minute
spines directed obliquely outwards.
S i z e . Diam. 35-40 g (W.).
Euastrum spinosum Hass. Fr. Alg. (1845), p. 884. Wolle
Desm. U.S. (1884), p. 106, t. 27, f. 4-7, 17.
Euastrum elegans, var. y Archer in Prit. Inf. (1861). Lundell
Desm. Sueo. (1871), p. 22.
Plate X X X V , fig. 5. a, living frond; b, empty frond ; c, d.
E u a s tz um in e zm e . Lund. Pesm. Suec. p . 20, t. 2 , f . 3.
Subelliptio, semi-cells subtriangular, apex somewhat protracted,
truncate, deeply incised, not dilated or dentate ; sides
bi-undulate, basal crenation most prominent, obtuse, and angle
obliquely truncate ; tumors three, inconspicuous and sometimes
wanting ; end view subelliptio, sides bi-gibbous ; side
view ovate. Cell membrane finely punctate.
S i z e . Diam. 32-88 g (W.) ; length 56 g ; diam. 32-35 g
(L.) ; length 19-55 g ; diam. 13-36 g (K.).
Wolle Desm. U.S. (1884), p. 104, t. 29, f. 6, 8 ; t. 27, f. SOSO.
Nordst. Norges Desm. (1878), p. 9.
Euastrum elegans ft inerme, Ralfs Desm. (1848), p. 89, t.
14, f. 7 e. Notari.s Desm. Ital. (1867), p. 87, t. 3, f. 17.
Grunow Desm. Austr. (1858), p. 501. Rabh. Alg. Eur.
(1868), p. 186. Jacobsen Desm. Donm. (1874), p. 191.
H ab. In pools.
Germany, Sweden, Norway, Denmark, Austria, Italy, United
States.
Plate X X X V ., fig. 4. a, living frond ; b, empty frond.
E u a s tz um liin a le . Palfs. Ann. Nat. Hist, (1844), xiv., g . 193, t. 7,
/■ 7.
Frond very minute, scarcely twice as long as broad, oblong ;
segments witli their basal portion either entire or bicrenate at
the sides, slightly contracted beneath the ends ; ends dilated,
not protuberant beyond the angles, its central notch acute,
broad ; transverse view with two lateral inflations, ends truncate,
angles rounded.
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