226 FRESB-WATEH ALG^ FROM BURMA.
The cells of tliis species are very little broader thnn long, and ai'e widest in the middle. The
zygospores are very eharacteristio, being elliptio-oblong in general shape, and exhibiting various
irregularly-disposed protuberances.
169. HVALOTHECA MOGOSA (Dillw.) Ehreub., 1840; Ralfs, Brit. Desm., 1848, p. 53,
t. 1, f. 2.
Hob. -Mansan^, near Hsipaw (No. 24193).
170. HYALOTHECA TINDULATA Nordst. iu Wif.tr. &Nordst. Alg. Essie., 1879, No. 2 4 8:
iasc. 21, 1889, p. 33.
Long. 13-4-16-3/^; lat. 6-7-7-7^.
Hob.—Mansang, neai- Hsipaw (No. 24193).
Genus: Desmidium Ag.
171. DESJUDIUJC SWARTZII Ag. 1824; Halfs, Brit. Desm., I848, p. 61, t. 4.
Long. 15-o-37'5a.; Jat. 2S-3V.
Ilab.—Mansang, near Hsipaw (No. 24193).
172. DESMIDIUM APTOGONDM Bi&b., 1836; Rabenh. Flor. Europ. AI-^ 1868 iii
p. 154. ° ' '
Apiogoimvt Desmidium Ralfs, Brit. Desm., 1848, p. 64, t. 32 f. 1.
Var. TETEAGONUM W. & G. S. West, Freshw. Alg. Ceylon, 1902, p. 193.
? Apiogomm tetrugonum Delp. Desm. subalp. 1878, p. 75, t. 3, f. 20-23.
Long, lo •5-17-5/^; lat. 20-31-5^. (PI. xii, fig. 5).
Ilab.—Mauaang, near Hsipaw (No. 24193).
Genus: Gymnozyga Elirenb.
173. GYMNOZYGA MONILIFOEMIS Ehreub., 1840.
Didymoprium Borrcri Ealfs, 1845; Brit. Desm. 1848, p. 58, t. 3.
JIah.—In springs on the river bank, Bhamo (No. 21501).
Order: PROTOCOCCOIDE^.
Family: CHAEAOIi;^.
Genus: Characium A. Br.
174. CHAEACIUJI PYHIFOEME A. Br. Alg. unicelL, 1855, p. 40, n. (
Fioi. Em-op, Alg. iii, 1868, p. 88.
Long. cell. 27^, cum stip. 40^; lat. cell. 15/x.
Mansang, near Hsipaw (No. 24193).
VB; Rabenh.
PEDIASTRUM. 227
Family: PLEtJROGOOOAGEi;.
Genus: Urococcus Kiitz.
175, UEOCOCCUS TEOPICUS sp. n. (PI. xi, figs. 17—21).
Cellulfe vegetativai magna-, subsphiericee, ellipse idea;, ovoideffi, pyrilbnnes vel
eubirregulares; membrana cellularum crassa et conspicue lamellosa, valde et excentrice
iiicrasaata; cellul« pauea? (usque ad 8) colouiam formautes, cellulis irregulariter dispositis
et stipitatis, stirpibus crassis irregularibus lamellosis et plu.s minus^e confluentibus.
Chromatoplioris valde granulosis, cum pyrenoidibus 1 vel 2 inclusis.
Propngatio cellularum divisione in omnes directiojies.
Long. cell. 19~36-5A'; lat. cell 13-33^; crass, membr. cell. 3-6M; diam. colon,
usque ad 158^^.
JIab.—Jn the Kan-gyi at Mudon (No. 24505).
This Alga is characterized by the thick-wallad cells, which are 8U[>ported singly or in small
colonies by hyaline stalks. These stalks are gradually developed and are very firm. They are
conspicuously lamellose and more lees irregular at the margin. The cells multiply by divisioc,
which may occur in any direction, but no colonies were observed consisting: of more than eight
cellsi Tlie cells soon break away from the small colonies, and each proceeds by cell-division nnd
the growth of the tough hyaline stalks to build up anew colony {tide PI. xi, figs. 17—19). The
stalks are colourless and very tough, and where a number of cells have been growing side by
side, they frequently coalesce at the ba-^e (PI. xi, fig. 21).
Tiie plant stands nearest to Hormoiila mucigena Borzi (Studi Algologici, i, Messina 1883), but
is distinguished by the much firmer integuments, which are nerer gelatinous, and by the larger
size and greater irregularity of the cells. The cell-wolU are also very much thicker and more
evidently lamellose. The disposition of cells and their aggi'egRtion into colonies is also quite
difierent. Moreover, Urococcm tropicus is aquatic in habit, whereas Eormoiila mwigena Borzi occnre
on wet rocks,
Zoogonidangia were not ohser^-ed.
The cbloroplast is large and very granular, almost entirely filling the interior of the cell, and
it contains one pyrenoid (or rarely two). None of the cells contained the red-brown pigment
which is so characteristic o£ the other species of this genus.
Family: HYDRQDIUTxAOE^-
Genus: Fediastrum Moyeii.
176. PEDIASTBUJ[ TETEAS (Ehrenb.) Ralfs in Ann. Mag. Nat. Hist, xiv, 1884,
p. 469, t. 12, f. 4.
Micrasieria.i Tcirafi Ehrenb.
Hab.—Mansnng, near Hsipaw (No. 24193). Between Thingan-nyi-naung and
Kawkareik, iu the side-channel of a stream (No. 24483).
177. PEDIASTEUM BORYANUM Menegh. Synops. Desm., 1840, p. 210 ; Ralfs, Brit.
Desm., 1848, p. 187, t. 31, f. 9«.
i/air.—Mansang, near Hsipaw (No. 24193).
All the specimens observed weie very rough.