48 ZYGOPHYCBiE.
M e so ta e n ium G r e y i. Turner Naturalist (1886), p. 34, t. 1 ,/. 1.
Frond cylindrical, smooth, straight, rarely curved, elongate,
no apparent constriction, not tapering at all towards the ends,
which are more or less broadly rounded.
S i z e . Length 76-104 p \ diam. 20-23 p (T-)-
H a b . In ro ck pools.
Yorkshire.
Plate X V I I I . , fig. 6, a, living frond; I I, empty fronds; after
Tnrner.
Genus 12.. T E TM EM O R U S . Ralfs. (1845).
Frond elongated, straight, cylindrical, or fusiform, constricted
at the middle; segments more or less tapering, not
inflated at the base; ends with an acute incision, the subdivisions
rounded, otherwise quite entire.
T e tm em o ru s B r eb is so n ii. Ralfs. Ann. N at. Nisi. (1844), xiv, t. 8,
f. 1-
Frond in front view with parallel sides, in lateral view
fusiform ; ends without any projecting processes ; puncta m
longitudinal lines.
S i z e . Diam. 18-20 p (W.) ; diam. 17-30 p (K.) ; length
194 p ; diam. 28 p (D.).
Ralfs. Desm. (1848), p. 145, t. 24, f. 1. Archer in Prit.
Inf. (1861), p. 746, t. 2, f. 12-13. Delponte Desm. (1878)
t 15 f 53-54. Cleve Sver. Desm. (1864), p. 492. Lundell
Desni. Suec. (1871), p. 76. Nordstedt Norges Desm. ^ 8 7 3 ),
p 39 Petit Liste Desm. Paris (1877), p. 29. Grunow
Desm! Austr. (1858), p. 501. Kirch Alg. Schles. _ (1878)_, p.
145. Wittrock Scan. Desm. (1869), p. 19. Brebisson Liste
D e sm . (1856), p. 145. Notaris Desm. Ital. (1867), p. 58, t.
6 f. 59. Eabh. Alg. Eur. (1868), p. 139. Jacobsen Desm.
Denm. (1 8 7 4 ), p. 179. Wolle Desm. U.S. (1884), p. 91, t.
20, f. 1-2, t. 5 0 ,1. 36.
Closterium Brebissonii, Meneg, Syn. Desm. (1840), p. 236.
Closterium monile, Kutz. Phy. derm. (1845), p. 132.
Penium striato-punctatum, Kutz. Spec. Alg. (1849), p. 168.
H ab. In ponds and pools.
Sussex, Kent, Surrey, Hants, Cornwall, Westmoreland,
Wales, Scotland ; France, Germany, Norway, Sweden, Denmark,
Austria, Italy, United States.
Plate X V I I I . , fig. 7. a, I, living fronds ; c, empty frond.
var, ft. tu rg id um , Ralfs. Lesm. (1848), p. 145, t. 24, f . 1, d e.
Larger, stouter, constriction deeper.
var. y. {Le Bary) Archer in P ritch. Infus. (1861),^. 746.
Smaller than either of the above, otherwise externally similar,
endoohrome in longitudinal fillets.
T e tm em o ru s g r a n u l a tu s . Ralfs. Ann. Na t. Nist. (1844), xiv.,
t. 8 ,/. 2.
Frond fusiform, both in front and lateral views, ending in a
colourless lip-like projection. Empty frond minutely punctate.
Zygospore orbicular.
S i z e . Diam. 88-50 p (W.) ; diam. 39-56 p (K .); length
122 ; diam. 43 p (D.).
Ealfs. Desm. (1848), p. 147, t. 24, f. 2. Archer in Prit.
Inf. (1861), p. 746. Hassall Fr. Alg. (1845), p. 378, t. 89,
I. 6. Delponte Desm. (1878), p. 188, t. 15, f. 55-56. Notaris
Desm. Ital. (1867), t. 6. Cleve Sver. Desm. (1864), p. 492.
Lundell Desm. Snec. (1871), p. 76. Nordstedt Norges Desm.
(1873), p. 39, Nordstedt Desm, Arct. (1875), p. 40. Wood
P. Water Alg® U.S. (1872), p. 117. Wolle Desm, U.S.
(1884), p. 91, t. 50, f. 33-34. Petit Liste Desm. Paris (1877),
p. 29. Wittrook Scan. Desm. (1869), p. 19. Brebisson Liste
Desm, (1866), p. 145. Notaris Desm. Ital. (1867), p. 58, t. 6,
f. 58. Eabh. Alg. Eur. (1868), p. 140. Jacobsen Desm.
Denm. (1874), p. 180. Kirch. Alg. Schles, (1878), p. 145.
Closterium granulatum, Breb. Meneg. Syn. Desm. (1840),
p. 286.
Penium ( TetmemorusJ granulatus, Kutz. Spec. Alg. (1849),
p. 167.
H ab. In ponds.
Sussex, Surrey, Hants, Kent, Gloucester, Lancashire, Westmoreland,
Cornwall, Wales, Scotland, Ire lan d ; France,
Germany, Sweden, Norway, Denmark, Italy, Russian Lapland,
United States.
Plate X V I I I ., fig. 8. a, h, living fronds ; c, empty frond.
Plate X IX ., fig. 1. Zygospore.
T e tm em o ru s laevis. Ralfs. Lesm. (1848),^. 146, t. 24, f . 3.
Frond in front view somewhat tapering, with truncate ends;
lateral view fusiform, empty frond without puncta, or very indistinct.
Zi'gospore at first quadrate, then oval, compressed.
S i z e . Diam. 20-22 p (W.) ; diam. 20-25 p (K.).
Brebisson Liste Desm. (1856), p. 145. Archer in Prit Inf.
(1861), p. 746. Nordstedt Norges Desm. (1873), p. 89.
Nordstedt Desm. Arct. (1875), p. 40. Grunow Desm. Austr.
4