Desmids from Thailand and Malaysia

26 M. HIRANO
18b. var. novae-silvae W.&G.S.West Pl.26, f.26.
West 1908, 3, 227, Pl.86, f.5-6; F6rster 1982, 173, Pl.36, f.7.
19.
L. 16.7 um, B. 14-23 ptm, and I. 3-5 #m. Sts. 31,32,44. Indonesia (Java), England.
New to Thailand.
C. borgei (Hirano) Croasdale Pl.18, f.17
Prescott et al. 1981, 2:3, 88, Pl.172, f.10,11. Syn. C. bioculatum Breb. var. borgei
Hirano 1968, Contr. Biol. Lab. Kyoto Univ. 21, 14, Pl.4, f.5.
L. 30-31 ptm, B. 23.8-24.6 ptm, and I. 5.7-7.5 ptm. St. 27. Japan, Europe, Alaska.
New to Thailand.
20. Cboergesenii Gr6nblad Pl.16, f.12,13.
Prescott et al. 2:3, 87, Pl.205, f.10.
L. 30 "m, B. 17.6 ptm, and I. 5 xtm. Cells small, approximately 1.5 times longer
than the breadth, deeply constricted, sinus narrowly linear; semicells subquadrate, basal
part of lateral margin prominently produced and rounded, apical angles broadly round-
ed, apex almost straight or slightly retuse at the middle; cell wall with a granule in the
centre of semicell. St. 47. Alaska. New to Thailand.
21. C. botrytis Menegh. var. botrytis
West 1911, 4, 1, Pl.96, f.1,2,5-15; F6rster 1982, 175, Pl.33, f.1-2.
L. 90 ptm, B. 68 ptm, and I. 26.5 gm. St. 18. Cosmopolitan.
21a. var. paxillosporum W.&G.S.West Pl.20, f.2.
Prescott et al. 1981, 2:3, 90, Pl.265, f.8,9.
L. 70.5-90 ptm, B. 59-68 ptm, and I. 24-26.4 ptm. Cells large, approximately 1.3
times longer than the breadth, constriction deep and sinus narrowly linear; semicells
truncate-pyramidate, lateral margin convex ane convergent, apex narrow and straight;
cell wall granulate, granules disposed at laterai margin and intramarginal, granular series
radial and concentric, central part of a semicell with an oblique and vertical series of
scrobiculations, the space between granules and scrobiculations smooth. St. 49. Europe,
U.S.A. New to Thailand.
22. C brasiliense (Wille) Nordst.
FOrster 1982, 177, Pl.29, f.11.
L. 25.5 ptm, B. 21 ptm, and I. 10 ptm. Ceils small, median constriction deep, sinus
open outward but acuminate at the extremity; semicells obversely and transversely
ovate, apex scarcely straight or flattened; cell wall covered with small granules regularly
disposed. St. 27. Brazil. New to Thailand.
23. C ceylanicum W. & G.S.West f. ceylanicum
West 1902, Trans. Linn. Soc. Bot. 6, 174, Pl.21, f.14,15; Krieger 1932, 173, Pl.11, f.9
(forma).
L. 33 #m, B. 27 pm, and I. 8 pt m. St. 23. Sri Lanka (Ceylon). New to Thailand.
23a. forma minus Scott&Prescott Pl.19, f.10; Pl.21, f.15.