^Ob FRESH-WATER ALG^ FROM BURMA.
101. COSMARIUM TKACnYDERMUM W. & G. S. West, Alg. Madag. 1893, p. 64,
t. 6, f. 36.
V a r . ELLIPTICDM vav. n. (PI. xv, fig. 18).
Var. semicellulis subellipticis, apicibus convesis.
Long. 52M; lat. 38-40M; lat. isthm. 19,.; crass. 25^.
Sab.—In springs on the river bank, Bhamo (No. 21501).
1 0 2 . COSMARIUM EENIFOEME ( R d l f s ) A r c h . in J o u r n . Bot. 1874, p. 92.
JIab.—In springs on the river bank, Bhamo (No. 21501).
1 0 3 . COSMARIUM LATUM Br6h. Liste Desm. 1856, p. 128, t. 1, f. 1 0 ; R o y &
Biss. Scott. Desm. 1894, t. 2, f. 10.
Cellulo? 1^-plo longiores quam l a t a ; semicellulce rectangukres, angulis inferioiibus
rotundatis et angulis snpeiioribus magis rotuudatis, apice levissiine retuso in medio;
grannlis subparvis, depressia ; a vertico visas oblougcc, poHs rotundatis.
Long. 68^; lat. 54^^; lat. isthm. 18/.; crass. 29'OM.
I f a i . — I n a small pool, Kyaukse (No. 22192).
The form seen was rather more rectangular than the general shape of C. latum, and the
granules •were slightly smaller and more numerous. Bat for its relative proportions it might aWost
have been placed under C. quadrum Lund. The granulation was very similar to that of 0. iullatum
Kordst., but there wore no piinctillations between the granules. Q. quadrum Lund,, C. lahm Breb.,
C. suUatum Nordst., C. orthnpleurum Roy & Biss., G. margaritalum (Land.) Eoy & Biss., and
C. consjJei'suni Ralfs are all species whioh require f u r t h e r investigation.
104. CosMAEiuM MULTIORDINATOM W. & G. S. "West, Welw. Afric. Freshw, Alg.
1897, p. 121, t. 3 6 7, f . 1.
V a r . BURMENSE v a r . n . ( P I . xv, fig. 19).
Var. angulis superioribus semicellularum leviter rotundatioribus, granulis paullo
majoribus et ad margines conicis.
Long. 77-83/x; lat. 09-5-64;^; lat. isthm. 19^; crass. 41,^.
Mansang, near Hsipaw (No. 24193).
This variety difiei-s chiefly in the somewhat larger size and conical form of the granules.
The conical granules are principally evident round the margins of the semioells, the granules in
the centre being more rounded. • The scrobioulations between the granules are email rounded pits,
and under no conditions of focus do they exhibit any angularity.
105. COSMARIUM SUBDECORATOM W. &. G. S. West, Desm. Singapore, 1897, p.
165, t. 8, f. 13.
Long. 60-64/t; lat. 50-52/^; lat. isthm. 16-17^.; crass. 28/^.
JIab.—In the Kan-gyi at Mndon (No. 24505).
106. CosMARiUM BTNUM Nordst. in Wittr. & Nordst. Alg. Exsic. 1880, No. 383 ;
et in fasc. 21, 1889, p. 39.
Var. crenis lateralibus 7-9, crenig apicalibus 4-6, tumore supra isthmum.
cum series verticalibus 5-7 granulorum circ. 8, et inferne cum serio
horizontali singula granulorum 5-6.
COSMARIUM. 207
Long. 46-49-5,x; lat. 34-5-37^; lat. isthm. 11-5—12/.; eras«. 27,^.
iTai.—In swamp, Katha (No. 22677). Mansang, near Hsipaw (No. 24198).
In the Kan-gyi at Mudon (No. 24505). Between Thingan-nyi-naung and Kawkareik,
in the side-channtìl of a stream (No. 24483).
C. bimtm appears to be a fairly common tropical species, and exhibits considerable variat
i o n in the number of lateral and apical orenations. The central tumour also varies in size, the
number of verfcioal series of granules ranging from five to sever. The basal series of granules
below the central tumour consisted of a single row in all the specimecs examined.
The form of this species described by Raciborski (Desm. No we, 1889, p. 93, t 5, t 25) f r om P o l a nd
also has a jeduced number of orenations and only one basal row of granules across the semiicells.
Specimens of C. binum from Burma and Ceylon resemble Eaoiborski's form, more than the original
Brazilian examples. An almost exactly similar form has been described by Borge from Queensland
as C. binum var. australiensis (cfr. Borge, Austral. Siisswasserchlor, 1896, p. 2 t. 3, f. 42).
107. CosMARiuM suBCKiiNATUM Ilantzsch in Rabenli. Alg. 1861, No. 1213,
Rabenh. Fior. Europ. Alg. iii, 1868, p. 164; Nordst. Desm. Arctoa;,
1875, p. 21, t. 6, f. 10, 11.
Forma paullo major; cellulas a vertice visse polis rotundatis.
LoDg. 4 V ; lat. 29-5-31-5/x. ; lat. isthm. 13^^; crass. 20/. (PI. xii, fig. 18).
Ilab.—In springs on the river-bank, Bhamo (No. 21501).
1 0 8 . CQSMARIUJI DICHONDBUM ^V. & G. S. W e s t , Alg. M a d a g . 1895, p. 65, t. 7,
f. 12.
Var. SUBHEXAGONUM var. n. (PI. xn, fig. 16).
Vtvr. semicellulis late trmicato-pyramidatis, angulis iuferioribus rotundatis,
angulis, superioribus leviter rotundatis, apico late truncato et recto; a
vertice vicis ellipticis. granulis magnis binis intra sed justa marginem
lateralem utrobique.
Long. 22ii; lat. 20/^; lat. isthm. 5-2^; crass. 12^.
Bai.—Momauk, east of Bhamo (No. 21551).
This v a r i e t y should be compared with C. Enabolkme "Wille var. pi-uiractum "W. & G. S. West,
which it resembles very much in the shape of tlie semicells.
1 0 9 . CoSMARIUM QUADRIVERRUCOSUM Sp. n, (Pi. XV, fig. 14).
C. parvunij paullo longius quam latam, profundissime coustrictum, sinu angustolineari
estremo subampliato ; semicellulfe late truncato-pyramidatie, angulis inferioribus
et supoiioribus rotundatis, lateribus convexis, apice leviter convexo ; membrana granulia
acutis subsparsc dispositis ornata, in ambitu circiter '14 ; verrucis magnis binis (leviter
5-angulatia) trans centrum semicellulanim ; a vertice visse ellipticce, verrucis magnis
truncato-retusis binis ad medium utrobique.
Long. 23^; lat. 21^; lat. isthm. 5-2/I ; crass, 15/x.
Jlab.—lw tlio Kan-gyi at Mudon (No. 24505).
110. COSMAEIUM TlUVEERUCOSUil Sp. M. ( P L XV, fig. 16).
C. parvum, piene 1^-plo longius quam latum, piofundisaime constiictum, sinu
angusto-lineari extremo anipliato; semiccllulce transverse oblongo-rectangulares, angulis
(K. EOY. BOT. G-AKD. CALCI I VOL. VI.