!* D E SM ID IU M SwARTzii.
Trimgular Desmidium.
1
I
Im
Class a n d O rd e r CRYPTOGAMIA ALGAD, Lin n -SA T . Ord. ALGAl, Juss.
G E N E R IC C H A R A C T E R .
Fila simpliaa, articulata, angulata,'angulis hyalinis crenatis, articulis demum
secedentibus.
Filaments simple, jointed, angular, the angles hyaline, crenate; joints at
length separating.
S P E C I F IC C H A R A C T E R .
D esmidium Swartzii; / & triangularihus, articulis hicrenatis.
D. filaments triangular, the joints bicrenate.
D e s m i d i u m Swartzii, Ag. Syst. Alg. p . g.
D iatoma Swartzii, Ag. Syn. p. 3 4 .-S v en si. Bot. t. 4 9 I. f. l,-3 .-L u n g b
Hyd. Dan. p. 177. t. 61. . O L-yngo.
ditches, in spring
and the begmmng o f summer. Appin, Captain Carmichael. ^
Plant forming a fine green, thin gelatinous fleece. Filaments simple, about
len f flexible, an inch or more in
ength, triangular, more or less twisted, the angles peUucid and colour-
less, while the centre is green. Joints mostly h a lf as broad as they are
with f a d h t l R r separating from each other
y. Before separation, the two crenatures o f each joint appear
to contract, and the articulation to be dissolved from the eircumfen
~ c h "a ::s r ^
stonf T t f r " imperfectly undeia
ffiann d describe the filaments
as plane; and indeed, till the genus BesmMum was established
by the former, the plant was referred to Diatoma. Cap-
tain C a r m i c h a e l , however, in one of his letters to me, oh-
serves, that the filaments are triangular; and he is strictly cor-
lect. Thus, the apparent anomaly ceases which so much surprized
LYNGBYE-that the joints, when detached, presented
292