A LGJ5 . 
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determined, is described under the name of Leptoctadia Binghamice . 
It has narrow, serrated fronds, with the aspect of Hymenocladia, 
but the structure of the cystocarpic fruit resembles that of Rhody- 
menia. Another puzzling plant, with a filiform frond, and having 
the habit of Callithamnion, but a structure resembling that of 
Rhodophyllis, is described under the name Erythroncema cera- 
mioides. It is an Australian species, collected by that keen-eyed 
algologist, M. J. B. Wilson. By the same collector a new species 
— S. marginata — has been added to the genus Sarcodia. It comes 
very near to S. Montagneana, but differs in having the cvsto- 
carps confined to the margin. 
A new species of Stenocladia, S. ramulosa , from Australia, is 
described as being a stouter plant than S. furcata , and having 
more corymbose branches. 
A plant, allied to this genus in structure, but of which the fruit 
is unknown, is placed in a new genus, Amylophora, in allusion to 
the great abundance of starchy granules in the frond. A curious 
case of the mimicry not unfrequent in Marine Algas, occurs in the 
new genus Peltasta, which might easily be mistaken for Acrotylus, 
both from its outward form and from the arrangement of its 
tetraspores. The interior structure, however, is totally different, 
consisting of rounded, angular cells, arranged like those of 
Rhodophyllis. The only species known is named P. australis. 
An Australian plant, A. hymenocladioides , which forms the type 
of the new genus Amphiplexia, in the Desmiospermeae, is placed by 
the author near Hennedya, on account of its exserted cystocarp. 
The genus Rhabdonia has undergone revision, and two new 
species have been added. One of these, R. compressa, from 
Tasmania, is remarkable for bearing so strong a likeness to 
Gracilaria compressa , that if collected in Europe it would pass 
for that plant, from which the structure of the frond and the 
zonate tetraspores at once distinguish it. The other species from 
Australia appears to be intermediate in character between R. 
mollis and R. hamata. 
The genus Eucheuma has likewise been passed in review, and a 
new species — E. jugatum — allied to E. serra, but with the primary 
spines verticillate, has been added. To this genus is also referred 
Mychodea Schrammi , Crn. To the genus Lejolisia, a new species, 
L. cegagropila (— Callithamnion cegagropila, J. Ag. Epicris), is 
now added. 
In revising the Rhodomelese, Dr. Agardh retains all the genera 
therein included in his “ Species Algarum,’' with the exception of 
Martensia, noth withstanding the opinion of Falkenberg, as ex- 
pressed in “ Bot. Zeit.,” 1881, p. 164. The constitution of the 
different tribes is, however, somewhat altered, Digenia being 
removed to the Chondriopsideae, and a new tribe, Rhodomelese, 
being made to include Rhodomela, Trigenea, and Odonthalia. The 
tribe Alsideae is omitted. Alsidium and the other remaining 
genera, with the exception of Bostrychia, which now comes in 
