186 FHESn-WATEE ALG^ PKOH BUBMA.
Fonila paullo miuor ; crass, cell, veget. 17/^; long, zygosp. 44-50^; lat. zygosp. 2ÒH-.
JIah.—111 springs ou the riror bank at Bliarao (No. 21501).
17. SriUOGVRA EXILIS sp. u. (PI. X, fjgs. 11-13).
S. cellulis vegetativis diametro 1^-4-plo longioribus, extremitatibus non replicatis;
chromatophoris 2, crassis, niarginibus irregularibiis, anfractibus l^-S; conjugatione
6calariformi, celhlis fructiferis non inflatis, sed cc-llulis vegetativis inter cellulas fructiferas
Eiulte inflatis ; zygospons oblongis cum polis valde rotundatis, nonnunquam paullo
irregularibus, cellulas friictiferas pfciie complentibus.
Crass, ceil, veget. 27-30>t ; crass, cell, inflat. inter eoli, fruct. 47-49/xj long,
zygosp. 86-45|tt; lat. zygosp. 27-50/i.
JIah.—In shallow pools, Singaing in Kyaxikse district (No. 22193).
T h e most remarkable feature of this Sph-ooya is the great inflation of those cells of the
female fiiameut -which have not succeeded iu conjugating. Sometimes these sterile, iuflated cells
alternate with ^he female gnmetaugia throughout the entire lengili of the conjugatiag filaments.
S. etilis should be compared -^-¡th S- dec'mim, from w]aich it is easily rfisfiaguished by its
uairoTrer filaments, thicker chloroplasts, and its oblong zygospores.
18. SPIKOGTEA LONGATA (Vouch,) Wittr. Goti. 01. sötv. Alg. 1872, p. 45; Petit,
Spirogyra Envir. Paiis, 1880, p. 20, t. 5, f. 4, 5.
Conjitgaia longata Vauch.
Zyynema lonqatum Hass,
Crass, coll. veget. long, zygosp. 49-51/^,; lat. zygosp. 28'5-31;t.
Hal Near tbe river at Bhamo (No, 2IÓ03).
1 9 . SPIROGYRA ORIICNTALIS sp. n. (PI. s , figs. 9, 10).
S. cellulis vegetativis diametro 3-5i-plo longioribus, estremitatibus non replicatis;
chromotaphoris 3, angustia, laxis, marginibus subintegris sed paullo irregularibus,
anfractibus 1 - l f ; conjugatione scaluriformi, ccllulis fructiferis multe inflatis;
zygosporis ellipticis, diametro circiter l-g-plo longioribus, polis leviter obtuse conicis,
cellulas fructiferas non com pi en tib us ; lamina mediana zygosporoí minute ser obic alata.
Ci-ass. cell, veget. 20-31/n; crass, coll. fructif. 57-65/^. long, zygosp. 61-5-67/^;
lat. zygosp. yS.-4¿/t.
Hab.—In springs on the river bank at Bhamo (No. 21501).
The greatly-inflated female gametangia oí this species arc verj- characterislie. It somewhat
resembles S. decintina, from which it diSsrs in its narrower filaments and in its inflated
fructiferous cells.
20. SPIEOGYEA DECiaisA (Miill.) Kütz. Phyc. germ. 1845, p. 223; Rabenh. Flor.
Europ. Alg. iii, 1868, p. 2422; Petit, Spirogyra Euvir. Paris, 1880,
p. 25, t. 8, f. 1-3.
Forraa cellulis vegetativis et zygosporis paullo niajoribus quam in forma typica
chromatophoris plerumque 3.
Crass, cell, veget. 42-í6^; long, zygosp. 73-92^»; lat. zygosp. 42-46^.
Uab.—Kyauktaga in the Pegu district (No. 22124). Also Singaing in the
Kyaukso district (No. 22193).
MOUGEOTIA. 187
The form of this species observed f r om Burma was slightly larger t h a n usual, and the number
of ohiomatophores was generally three. It was almost identical with specimens examined from
•Koh Chang in the Gulf o£ Siam, but the vegetative ceUa were slightly thinner. It is one of
t h e commonest tropical species of the genus, and is subject to muoh variation, A species described
by Sohmidle (Alg. aus Nyassa See, 1903, p. 76, t. 3, f. 2) S. Fullehornci is probably referable
t o 8. decimim. The only dilference is in the somewhat narrower chloroplasts,
Var. PI.ENA var. n. (PI. x, figs. 6-8).
Var. cellulis vegetativis paullo latioribus et brevioribus, diametro l|-2-plo
longioribus; zygospons cellulas complentibus.
Crass, cell, veget. 38-44;^; long, zygosp. 64-73^^; iat. zygosp. 40-14;^.
JJah.—in flooded rice-fields, Burdwan (No. 24674).
21. SPIROGYRA NEGLECTA (Hass.) Kiitz. Spec. Alg, 1849, p. 441 ; Rabenh, Fior.
Europ. Alg. iii, 1808, p. 248; Petit, Spirogyra Knvir. Paris, 1880,
p. 5i6, t. 9, f, 1-5.
Zygnema mgleata Hass.
Forma cellulis vegetativis paullo crassioribus.
Crass, cell, veget. 66-72« ; long, zygosp. 02-95/^ ; lat. zygosp. 62-63;^ ; diam.
aplanopor. spheric. 45-49/i.
i7ai.—Kyauktaga in the Pegu district (No. 22124).
a'he specimens observed were very slightly larger than usual, but otherwise exactly typical.
I n some of the filaments globular aplanospores were noticed.
22. SPIROGYRA MAXIMA (Hass.) Wittr. in Wittr. & Nordst. Alg. Exsic. 1882,
No. 400.
Zygnema maximum Hass. in Ann. Mag. Nat. Hist. 1842, p. 36.
Zygnema nrhiculare Hass. Brit. Freshw. Alg. 1845, p. 138, t. 19.
Spirogyra orbicularis llass. Kiitz. Spec. Alg. 1849, p. 442; Petit, Spirogyra
linvir. Paris, 1880, p. 31, t. 12, f, 1-2.
Grass, coll. veget. 121-150/x ; diam zygosp. 100-120^; crass, zygosp. circ. 82/^.
I7ai.—Near the river at Bhamo (No. 21503).
A large sterile species, probably maxima, was observed from Haipaw
(No. 24120). Smaller sterile species were observed from Vizagapatam (No. 17916),
Lashio (No, 22557) and the river Irrawaddy at Thayctmyo (No. 22999).
Genus : Mougeotia Ag.
2 3 . MOUGEOTIA LAETEVIRENS (A. B r . ) W i t t r.
Craterospermum Icstevirena A. Br. Alg. 1855, p,
p. 81, t. 3, 1 1-13.
CrauB. cell, veget. 21-23^4 ; lat. spor. 32^.
Kyauktaga ia the Pegu district (No. 22124).
DeBary, Conj. 1858,