Siz e . Length 75 p \ diam. 38-65 p (Wo.).
Ralfs Desm. (1848), p. 141, t. 23, f. 3. Archer in Prit.
Inf. (1861), p. 742. Lundell Desm. Suec. (1871), p. 68.
Nordstedt Norges Desm. (1873), p. 33. Brebisson Liste
Desm. (1856), p. 138. Notaris Desm. Ital. (1867), p. 49, t.
4, f. 39. Wolle Desm. U.S. (1884), p. 143, t. 45, f. 24, 25.
Rabh. Alg. Eur. (1868), p. 217. Jacobsen Desm. Denm.
(1874), p. 207.
Staurastrum aculeatum, Ralfs Ann. Nat. Hist. (1845), xv.,
p. 156, t. 11, f. 4.
Goniocystis {Trigonocystis ?) aculeatum, Hass. Fr. Alg.
(1845), p. 353.
Staurastrum aculeatum, var h. controversum, Rabh. Alg. Eur.
(1868), p. 217. Wille Norges Desm. (1880), p. 44.
H ab. In ponds.
Surrey, Sussex, Gloucester, Westmoreland, Cornwall, Wales,
Scotland ; France, Sweden, Norway, Denmark, Italy, United
States.
Flate L X ., fig. 1. a a, living fronds; h, empty frond; c d, end
views; e, zygospore.
S tauzastzum a cu le a tum . Meneg. Syn. Lesm. (1840), p. 226.
Frond spinulose ; segments with a short process on each side
terminated by minute spines; end view with three to five
straight rays, terminated by spines. Zygospore globose, armed
with long spines, forked or dichotomons at the apices.
Siz e . Length 45-48 p ; diam. 35 p (N.). Length 36 p-,
diam. 54 p (D.). Diam. 34-50 p (K.). Diam. without spines
50 p (Wo.).
Ralfs Desm. (1848), p. 142, t. 23, f. 2. Kirchn. Alg.
Schles. (1878), p. 166. Archer in Prit. Inf. (1861), p. 742.
Delponte Desm. (1878), t, 13, f. 3-5, Cleve Sver. Desm.
(1864), p. 490. Lundell Desm. Suec. (1871), p. 68. Nordstedt
Norges Desm. (1873), p. 33. Petit Liste Desm. Paris
(1877), p. 31. Brebisson Liste Desm. (1856), p. 138. Rabh.
Alg. Eur. (1868), p. 217 in part. Wille Nov. Zem. (1879),
p. 54. Wille Norges Desm., p. 44. Schaarsohm. Magy.
Desm. (1883), p. 274. Mask. New. Zeal. Desm. (1882), p.
244. Nordstedt Desm. Spitz. (1872), p. 40. Jacobsen Desm.
Denm. (1874), p. 207 partly. Wolle Desm. U.S. (1884), p.
140, t. 45, f. 1-3.
Desmidium aculeatum, Ehr. Inf. (1838), p. 143, t. 10, f. 12.
Phycastrum aculeatum, Kutz. Phyc. Germ. (1845), p. 138.
Goniocystis {Trigonocystis) aculeatum, Hass. P. W. Alg.
(1845), p. 353, t. 84, f. 12.
H a b . In ponds.
Sussex, Hants, Westmoreland, Wales: Prance, Germany,
Sweden, Norway, Denmark, Nova Zembla, Italy, Hungary,
United States, New Zealand.
Plate L X .,fig . 2. a, living fro n d ; I, empty frond ; c d, end views.
S tauzastzum v e s titum . P a lfs Lesm. (1848), p. 143, t. 23, f . 1.
Frond rough with minute emarginate spines; segments fusiform
; end view triradiate, eaob side having two spines, short
slender, and often accompanied by other smaller ones.
Siz e . Length 64 p ; diam. 43 /x (D.) ; length 41 p ; diam.
63-78 p (K.) ; diam. 62-90 p (Wo.).
Archer in Prit. Inf. (1861), p. 742, t. 3, f. 80, 81. Delponte
Desm. (1878), t. 13, f. 46-49. Cleve Sver. Desm. (1864), p.
491. Lundell Desm. Suec. (1871), p. 68. Kiroh. Alg.
Schles. (1878), p. 167. Nordstedt Norges Desm. (1873), p.
31. Petit Liste Desm. Paris (1877), p. 31. Brebisson Liste
Desm. (1856), p. 137. Rabh. Alg. Eur. (1868), p. 219 / n e
var. b.). Jacobsen Desm. Denm. (1874), p. 207. Wille
Norges Desm. (1880), p. 46. Lemaire Desm. Vosg. (1883),
p. 24. Nordst. Desm. Bras. (1869), p. 230. Wolle Desm.
U.S. (1884), p. 188, t. 45, f. 28-80.
H a b . In ponds, &c.
Sussex, Lake District, Wales ; France, Germany, Sweden,
Norway, Denmark, Italy, Brazil, United States.
Plate L X ., fig. 3. a, living frond ; b, empty frond; c d, end views.
S tauzastzum o x y a c a n th um . Archer in Pritch. Infus. (1861\
p. 742.
Segments in front view broadly fusiform, rough with minute
granules, furnished on the outer margin with six subulate acute
depressed spines (four of which are apparent in this view), processes
elongate incurved, the granules thereon arranged^ m
transverse lines terminated by 3 or 4 minute spines ; end view
triradiate, the processes elongate, straight sides somewhat concave,
end furnished at the middle with a pair of very slender
extremely acute subulate spines projecting to each side.
Siz e . Length 29 p ; diam. 40 p (L.).
Lnndell Desm. Snec. (1871), p. 67. Eabh. p j p t - J l .
Sachs. (1863), p. 193. Rabh. Alg. Eur. (1868), p. 219.
Nordst. Desm. Gronl. (1885), p. 11.
H a b . In pools.
Lake District ; Sweden, Greenland, Germany.
Plate L X ., fig. 4. a, liviiig frond ; b, empty frond ; c d, end views-
I I