42. H Y D R U R U S Ag.
Char. Frond gelatinous, cijlindrical, branched, solid, filled
with scattered, oviform, bright green granules.
Derivation. From vBaxp, water, and ovpa, a tail.
1. H tdrurus D ucIaUzelii Ag.
Plate L X X V I I . Fig. 3.
Char. Frond verg gelatinous, branched, plumose.
Ag. Consp. Crit. Diat. p. 27. Batrachospermum Mgosurus
Ducluz. Palmella Mgosurus Lyngb., Dan. t. 68.; Harv.
in Manual, p. 180.
Hab. In alpine rivulets, on stones, &c. In the river
Walkam, near Tavistock: Mr. Ralfs. Meary, Devon :
Rev. W. S. Hore.
“ Root scutate, blackish, rather hard. Fronds clustered,
solid, very gelatinous, 2—6 inches long or more, 2—4 lines
in diameter, cylindrical, freely waving in the water, attenuated
towards the apex, branched; branches scattered,
alternate, elongate, slender, beset with other more slender,
short ramuli. Gelatinous mass pellucid, viscid, colourless
under the microscope, without apparent margin, unless as
the granules imbedded within its substance indicate such ;
these are globose, green, formed in the stem and primary
branches, most densely set in the ramuli, especially towards
the margin. Colour of the recent frond brownish-olive, or
dark brown, in drying, green ; of the granules both recent
and dry, green.
“ The odour, in a recent state, is very offensive, and as
Lyngbye remarks, only to be submitted to hy an algologist.
In a dry state it shrinks much, and most closely adheres to
paper. Having only seen this very interesting plant in a dry
state, I have thought it better to copy the above description
from Lyngbye. Our specimens, so far as they can be examined,
well agree with his figure. The affinities of the genus
are doubtful. By Agardh it is now placed near Schizonema,
to which its offensive smell certainly allies it. B u t the form
and appearance of the granules are so totally unlike the frus-
tules of any diatomaceous plant, that, for the present at
least, I retain it near Palmella, to which it seems to me
about as much allied as Choetophora endivioefolia to the shapeless
species of that genus. I f a true diatomaceous plant. It
ought, as Agardh suggests, to form the type of a new series,
of which, perhaps, our Cgmhella loetevirens might represent
the lowest form.” — Harv.
There is not the least question but tha t the Hgdrurus
Ducluzelii is not a diatomaceous plant, and it is equally clear
that it is an undoubted member of the family of the Ulvacece,
In some measure connecting Ulva with Enteromorpha. The
granules are oviform, precisely resemble zoospores, with
which in function it is difficult to conceive tha t they are not
identical, the thin being transparent.
Section ii.
Frond reticulate.
43. E N T E R OM O R PH A Linh.
Char. Frond tubular, hollow, membranaceous, and o f a reticulate
structure. Fructification consisting o f three or
fo u r granules aggregated in the reticulations.
Derivation. From svrspov, the entrail, and gopf>y, a fo rm
or appearance.
1. E nteromorpha int est inal is Link.
Plate L X X V I I . Fig. 2.
Char. Fronds elongated, simple, infiated, often fioating.
Grev. Alg. Brit. p. 179.; W y a tt, Alg. Dar. No. 80.
E. B. 2756. ; Harv. in Hook. Brit. Flor. p. 313. ; et in
Manual, p. 174. E . lacustris Hassall, in Trans, of Lin-
nsean Society.
Hab. In ditches. Common, summer and autumn.
diÉ