particulars. The genera Ochlochoete, Bulbochoete, and Coleochæte,
are very closely allied to Tiresias, Bory, {OEdogonmm, Link ; Vesi-
cudifera, Hassall,) and bear the same relation to it that Braparnal-
dia, Chætophora, and Stygeoclonium do to the genus TJlofhrix, of
Kiitzing, {Sphoeroplea, Berk., Lyngbya, Hassall). In the former
of these two groups of plants the setæ, when present, are rigid
continuous tubes ; and the fruit, so far as has been observed, is
not contained within an original cell of the filament, but each
sporangium is in a new cell, formed, it is true, by the elongation
of an original cell, but subsequently separated from it by a
septum : this occurs in Tiresias, Bulbochoete, and Coleochæte. In
Draparnaldia, on the contrary, and its immediate allies the
diaphanous prolongations of the filaments are septate, each consisting
of a series of elongated cells. The sporangia, also, in
Draparnaldia glomerata, Ag., and Chætophora elegans, Ag., in
which species we have observed them, are formed within the original
cells of the ramuli, causing the latter to assume a moniliform
appearance. Quaternate opseospermata, which are most probably
gemmæ, likewise occur in these species, as well as in those of
the genus Stygeoclonium of Kützing.
[I am indebted to Mr. Thwaites for the above description, and
for a beautiful figure from which our plate has been prepared.—
W.H.EA
Fig. 1. Fronds of OcHLO0HiET.B h y s t k i x :— natural dze. 2. The same, iMsy-
nified. 3. Small portion of a frond:—ve>y A "