Ealfs. Brit. Alg® Exs. No. 29. Archer in Prit. Inf. (1861),
p. 749. Cleve Sver. Desm. (1864), p. 495. Lundell Desm.
Suec. (1871), p. 77. Nordstedt Norges Desm. (1873), p. 40.
Petit Liste Desm. Paris (1877), p. 28. Wittrock Scan. Desm.
(1869), p. 23. Brebisson Liste Desm. (1856), p. 153.
Cloatenuin striolatum, var. ß. intermedia, Jacobsen Desm.
Denm. (1874), p. 176.
Closterium intermedium a. typicum, Klebs. Desm. Pruss.
(1879), p. 16.
Closterium striolatum, var. h., elonqatum, Rabh. AK. Eur.
(1868), p. 126.
H ab.
Wales; France, Germany, Sweden, Norway.
Flate X L , fig. 2. a, living c e ll; b, empty cell.
Flate X V ., fig. 6. Empty cells.
C lo s te r ium a n g u s t a tu m . Kutz. Fhyc. Germ. (1845), y;. 132.
Frond slender, ten to twenty times as long as broad, sub-
linear, slightly curved, scarcely attenuated, upper margin convex,
gradual, lower concave j ends truncate, slightly rounded ; large
granules in a single series; empty frond pale reddish, especially,
near the ends, stri® few (about four), very distinct, transverse
sutures usually three.
S i z e . 0-4 mm. x 2 1 p (R.) ; diam. 15-25 p (W . ) .
Ralfs. Desm. (1848), p. 172, t. 29, f. 4. Archer in Prit.
Inf. (1861), p. 749. Wolle Desm. U.S. (1884), p. 40, t. 6, f.
21-23. Lundell Desm. Suec. (1871), p. 78. Nordstedt
Norges Desm. (1873), p. 40. Petit Liste Desm. Paris
(1877), p. 28. Wood F. Water Alg® U.S. (1872), p. 110.
Wittrook Scan. Desm. (1869), p. 23. Brebisson Liste Desm.
(1856), p. 153. Notaris Desm. Ital. (1867), p. 66, t. 8, f. 72.
Rabh. Alg. Eur. (1868), p. 126. Jacobsen Desm. Denm.
(1874), p. 176.
Closterium sulcatum, Breb. in litt, fide Ealfs.
H a b . In ponds.
Sussex, Surrey, Westmoreland, Wales, Scotland ; Prance,
Germany, Norway, Sweden, Italy, Denmark, United States.
Flate X I ., fig. 3. a, living cell; I, empty cell; c, portion enlarged.
C lo s te r ium J u n c id um . Ralfis. Lesm. (1848), p. 172, t. 29,f . 6.
Frond very slender, fifteen to even thirty-five times as long as
broad, linear, straight, except towards the extremities, which are
somewhat curved downwards, ends obtuse, empty frond nearly
colourless, stri® not numerous, fa in t; transverse sutures usually
three. Zygospore orbicular, smooth.
S i z e . 0'22-0'37 mm. x 5 p (R .) ; 0-22-0-46 mm. x 7-
14 p (D.). Diam. 11-12 p (W.).
Wolle Desm. U.S. (1884), p. 38, t. 6, f. 2, 3. Archer in
Prit. Inf. (1861), p. 749. Delponte Desm. (1878), p. 115, t.
17, f. 11-14. Cleve Sver. Desm. (1864), p. 495. Lundell Desm.
Snec. (1871), p. 78. Nordstedt Norges Desm. (1873), p. 40.
Nordstedt Desm. Arct. (1875), p. 39. Petit Liste Desm. Paris
(1877), p. 28. Grunow Desm. Austr. (1858), p. 501. Wood
F. Water Alg® U.S. (1872), p. 110. Wittrock Scan. Desm.
(1869), p. 23. Brebisson Liste Desm. (1856), p. 152. Notaris
Desm. Ital. (1867), p. 64, t. 7, f. 69. Eabh. Alg. Eur. (1868),
p. 127. Jacobsen Desm. Denm. (1874), p. 176.
Closterium intermedium c. juncidum, Klebs. Desm. Pruss.
(1879), p. 16.
H ab. In ponds.
Sussex, Cheshire, Westmoreland, Cornwall, Wales ; France,
Germany, Italy, Sweden, Denmark, Norway, Austria, Russian
Lapland, United States.
var. ¡3. Frond stouter, less elongated.
Closterium juncidum, var. (3, Ralfs. Desm. p. 173, t. 2967
H ab. In ponds.
Sussex, Wales.
Flate X I I I . , fig. 7. a, living cells ; I, empty cells ; o. zygospore.
C lo s te rium lin e a tu m , Ehr. A lh . Berl. Akad. (1833), y;. 238.
Frond slender, elongated, eighteen to twenty or twenty-five
times as long as broad, gently curved, very gradually attenuated,
upper margin unequally convex, being most curved near the
ends, lower concave, or somewhat protuberant at the centre,
sides somewhat parallel for a portion of their length, extremities
gradually tapering, slender, curved downwards, ends obtuse ;
large granules in a single series, empty frond reddish, stri®
numerous, distinct, one or more transverse lines at the suture.
Zygospore double, rounded, smooth.
S i z e . 0-5 mm. x 26 p (R.) ; 0'43-0-72 mm. x 21-28 p
(D.). Diam. 24-36 yx (W,).
Ehr. Infus. (1838), t. 6, f. 8. Wolle Desm. U.S. (1884),
p. 43, t. 6, f. 16. Archer in Prit. Inf. (1861), p. 749, t. 3,
f. 41,42. Hassall Fr. Alg. (1845), p. 872. Ealfs. Desm.
(1848), p. 173, t. 30, f, 1. Delponte Desm. (1878), p. 117,
t. 17, f. 28-30. Cleve Sver. Desm. (1864), p. 495. Lundell
Desm. Sueo. (1871),p. 79. Wood F. Water Alg® U.S. (1872),
p. 112. Brebisson Liste Desm. (1856), p. 152. Rabh. Alg.
Eur. (1868), p. 130. Jacobsen Desm. Denm. (1874), p. 174.
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