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REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 111
this statement by our own observations, although Koschtsug maintains the contrary. The genus
Bangia, except that the cells composing the frond are arranged in cylindrical filaments instead of
expanded membranes, differs in no essential respect from Porphyra and the production of spores and
antherozoids is the same.
The development and structure of the species of this order have formed the subject of a number of
important papers, viz: Porphyra laciniata, in Études Phycologiques, by Bornet and Thuret; Études
Anatomiques sur les Porphyra, by Janczewski, in Annales des Sciences, Ser. 5, Vol. XVII; and Ueber die
Geschlechtspflanzen von Bangia fusco-purpurea, in Pringsheim’s Jahrbücher, Vol. II. In the Nereis.
Am. Bor., Harvey placed Porphyra and Bangia with the Ulvaceæ, which they resemble in so far as they
consist of simple membranes and filaments some of whose cells change directly into spores. The sporee
[sic] of the Porphyreæ, however, are motionless bodies, not zoospores as in the Ulvaceæ, and their color
is not green, but brownish red. The systematic position of the order has been in doubt, because,
although there were well-known spores and bodies to which the name of antheridia was applied, no one
had succeeded in detecting trichogynes and procarps, which must necessarily exist if the Porphyreæ are
to be classed with the Florideæ. Dr. G. Berthold, however, has recently published in the Mittheilungen
aus der zoologischen Station zu Neapel a communication in which he claims to have discovered
trichogynes in species of Bangia and Porphyra. According to him, the cells produce short trichogynes to
which the antherozoids adhere, and as a result the contents of the cell divide and produce the spores at
once. In other words, the Porphyreæ are the simplest of the Florideæ; a vegetative cell produces a
trichogyne and is itself the carpogenic cell from which the spores are formed. Dr. Berthold goes further
and says that some of the spores are nonsexual and are true tetraspores, but his article is not
accompanied by illustrations. Bornet, to a certain extent following Cohn, suggests a possible connection
of the Florideæ with the Phycochromaceæ by means of the Porphyreæ. Admitting that Erythrotrichia
and Goniotrichum are related to Porphyra and Bangia, we have in Goniotrichum algæ composed of
rose-colored discoid al cells packed in a thick gelatinous tube, from which they escape much as in some
of the Phycochromaceæ.
PORPHYRA, Ag.
(From πορφυρα [porphyra], a purple dye.)
Fronds gelatinous, membranaceous, composed of a single layer of brownish-red cells,
those near the base sending out root-like processes; spores borne near the margin of
frond, eight arising from a single mother-cell; antheridia marginal, consisting of 32-
64 spherical, colorless antherozoids.
A small genus, the species of which are characterized by the relative position of the spores and
antheridia and by the shape of the frond. Most of the species have been founded on variations in the
outline of the frond, and recent writers agree in uniting many of the species of the older algologists.
P. LACINIATA, Ag.—Laver. (P. linearis, Grev.; Phyc. Brit., Pl. 211, Fig. 2.—P.
vulgaris, Harv., Phyc. Brit., Pl. 211, Fig. 1.—P. laciniata, Harv., Phyc. Brit., Pl. 92;
Études Phycol., Pl. 31.)
Fronds three inches to a foot and a half long, persistent throughout the year, color
livid purple, substance gelatinous but firm, at first linear, but becoming widely
expanded and finally much lobed and laciniate; antheridia and spores forming a
marginal zone, usually borne