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REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 137
single at the nodes, numerous, usually unicellular, often ending in irregular disks;
tetraspores in a circle at the nodes, immersed in the cortical cells; favellæ?
Forming tufts on mud-covered rocks at low tide.
New Haven, Prof. Eaton; near New York, Mr. Young; Newport‚ R. I.; common from
Nahant to Eastport.
This species is not, as Harvey and Agardh supposed, very distinct, but, on the contrary, can scarcely be
distinguished from C. Deslongchampsii, except in the tetraspores, which are immersed, not projecting
as in that species. Both species inhabit similar localities, both are deep purple in color, are procumbent
at the base, and have numerous rhizoids; the branching and erect tips are the same in both.
Furthermore, as it occurs with us, C. Hooperi not unfrequently bears precisely such irregular botryoidal
masses as are found on C. Deslongchampsii in Europe, and which are figured in the Phycologia
Britannica. Harvey, as well as Nægeli and Cramer, doubts whether these masses are really favellæ,
and, judging from American specimens, they are more probably monstrosities. In one case we found the
distortions on a specimen bearing tetraspores, and Nægeli and Cramer have observed a similar case, a
presumption against the favelloid nature of the swellings. Fully-matured tetraspores are to be desired,
and it may be that they will be found to be prominent, as in C. Deslongchampsii, in which case the
validity of the species would be more than doubtful.
C. FASTIGIATUM, Harv., Phyc. Brit., Pl. 255.
Fronds lake-red, densely tufted, two to five inches high, filaments capillary,
dichotomous throughout, divisions erect, level-topped, apices erect or slightly
incurved; tetraspores secund on the outer side of the branches, prominent; favellæ
small, lateral, with a short involucre.
On Zostera.
Massachusetts Bay; Greenport; Newport; Long Branch, Harvey.
This species is at present a puzzle. In American herbaria one frequently finds specimens labelled C.
fastigiatum, and some specimens bear Harvey’s own handwriting. Unfortunately, the species is
persistently sterile, for we have only twice found tetraspores in what seemed to be this species, and
sterile specimens are hardly sufficient for determination in the genus Ceramium. What was apparently
considered by Harvey to be his C. fastigiatum is common south of Gape Cod and forms beautiful tufts
on Zostera. The color is a lake-red, the filaments are all capillary and regularly dichotomous, the upper
segments being level-topped, so that when spread on paper the species has a regular outline. The apices
are erect, not rolled inwards at the tip, and short rhizoidal processes are given off from some of the
nodes. Harvey states that the tetraspores are prominent and secund on the outer edge of the branches,
while Agardh says they are whorled at the nodes. In one specimen we found them as described by
Harvey. It must be admitted that when sterile the species approaches too near C. tenuissimum, and it
is much to be desired that a large set of fruiting specimens be examined to settle the disputed question
of the tetraspores. C. fastigiatum is a species apparently not well known to continental botanists, who
seem to have at times included it in other species without reference to British specimens. With us it is
common, although, considering that there may be a doubt about the determination, we have only
quoted the localities given by Harvey. By Agardh C. fastigiatum is considered closely related to C.
Deslongchampsii, but judging by Harvey an specimens, both from Ireland and New England, we can
hardly think that the two species are immediately related.