Flora Desmidiarum Japonicarum IV

•186 Minoru HIRANO : Flora Desmidiarum Japonicarum
utrobique et polis leviter acute rotundis. Long. 15.4-16.8pa, Lat. 15,4-16pa,
Lat. isth. 6.4-7pa.
.Hab. H6kkaido: Kiritappu in Kushiro. Hondo : Hachimantai in Mutsu ;
Mt. Kurikoma in Ugo; Ojiroi in Iwaki; Ozegahara in K6zuke ;• Happ6-ridge,
Mt. Kirigamine in Shinano; Ishigaki-ike in Ise; Fuse-ike, Mt. Hira in Oomi.
,(Pl. XXVII, f. 26)
Distr. Japan, Europe.
I am not certain whether this species is a true Cosmarium vogesiacum
or is an other species since I have not seen the LEMAiRE's original paper.
According to the MEssiKoMMER's figures on the Viertelj. NaturÅí Ges.
Zurich Vol. 80, pl. 4, f. 54 and pl. 5, f. 56 the semicell is elliptic-pyramidate
in forrn and the granules are disposed in somewhat irregularly two radial
series within around the margin, while in our forms the granules are
disposed in a somewhat transverse series across the face of the semicell,
about three series are visible, and two large gtanules are at the centre.
Another noteworthy species is Cosmarium biPunctatum that is trapezoid
semicell. This species has a radial series of granules within the margin
and two Iarge granules at the centre of semicell. Both species are similar
each other in disposition of granules and in having the central large
granules, but the form of sernicell is quite different. This species is not
common in our country, and is found at the margin of marshes or peaty
bogs of lowland and upland.
Cosmarium dichondrum W. & G. S. WEsT in Trans. Linn. soc. Bot• 5, 65, 1895;
KRIEGER Arch. HydrobioL suppL 11, 175, 1932.
Cellulae parvae, leviter longiores quam latiores, profunde constrictae,
sinu angusto-lineari extremo leviter ampliato; semicellulae elliptico-subtra-
peziformes, angulis apicalibus et basalibus obtusis, apice truncato et recto ;
membrana minute granulata, granulis in serie radiali ordinatis, cum
granulis duobus magnis prominentibus ad centrum juxta infra apicem; a
latere visae circulares, lateribus cum prominentibus granulis prope apicem
utrobique; a vertice visae ellipticae, lateribus cum granulis duobus ad
medium utrobique. Long. 19.6pa, Lat. 18.2pa, Lat. isth. 7pa.
Hab. Hokkaido: Horomui in Ishikari. (New to Japan) (Pl. XXVII, f. 20)
Distr. Sumatra, Bali, Madagascar.
var. subhexagonum W. & G. S. WEsT in Ann. Roy. Bot. Gard. Calcatta- 6, 207,
1907.
Semicellulae late. truncatQ-pyramidatae, .marginibus lateralibus convexis
convergentibus, angulis basalibus rotundis, angulis apicalibus obtusis, apicibus