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130 THE MARINE ALGÆ OF NEW ENGLAND. One of the commonest and most beautiful of the genus south of Cape Cod, but only known in one locality north of the Cape. It is often brought up on fishermen’s nets, and, as a rule, inhabits deeper water than most of the genus. It often attains the height of four or five inches, and is broadly pyramidal in outline. The main branches are rather stout and distinctly corticated, but the ultimate ramifications are very soft and flaccid. With us seirosporic specimens are very common, making the species easily distinguishable, but no form of tetraspore or bispore has been observed on American specimens. According to Bornet, tetraspores, bispores, and seirospores sometimes occur on the same individual. From a comparison of our plant with authentic European specimens there can be no doubt of the specific identity of the two. Accepting the account of the cystocarps given by Bornet, it is extremely doubtful whether the species should be kept in the present genus, and perhaps the genus Seirospora should be restored, not, however, as originally adopted by Harvey. SPECIES INQUIRENDÆ. C. TENUE, Harv., Ner. Am. Bor., Part III, p. 130. (Griffithsia tenuis, Ag.) Filaments tufted, ultra-capillary, irregularly much branched, diffuse, flexuous, the branches and their divisions very generally secund, springing from the middle of the internodes; ramuli few and distant, patent, filiform, beset toward the attenuated apices with whorls of minute byssoid fibers; articulations cylindrical, those of the branches 4-6 times, those of the ramuli 3-4 times as long as broad, and gradually shorter towards the extremities. Beesley’s Point, N. J., Harvey. Two specimens which can probably be referred to the present species have been received from Nantucket, one presented by Mrs. Lusk, the other by Mr. Collins. In the absence of fruit the genus cannot be determined. Nægeli, in Beitrage zur Morphologie und Systematik der Ceramiceæ, says that the tetraspores are terminal on a single-celled pedicel. According to Harvey, the species is distinguished by the branches, which are all given off from the middle of the internodes of the branches of the preceding grade, Nægeli says that this species has normal branches like those of Griffithsia barbata, and he regards those given off from the internodes as adventive branches. C. TOCWOTTONIENSIS, Harv. MSS., fide Bailey. Providence, Bailey; Warwick, Hunt. As far as we know, this species, mentioned by S. T. Olney in his List of Rhode Island Plants, fortunately for pointers and the throats of American algologists, has never been described. GRIFFITHSIA, Ag. (Named in honor of Mrs. Griffiths, of Torquay.) Fronds filiform, monosiphonous, without cortications, dichotomously branching, branches of two kinds, the vegetative of indeterminate, the fructiferous of determinate growth; antheridia sessile and covering the upper surface of the terminal cells in tufted whorls at the nodes, or in densely whorled pyramidal tufts on involucrate branches; tetraspores
REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 131 tripartite, clustered in involucrate whorls at the nodes or on the inner side of short fascicled branches; cystocarps (favellæ) involucrate. A beautiful genus, comprising between 30 and 40 species, but only represented on our Eastern coast by a single species and on the Western coast by two doubtfully determined species. The genus is distinguished from Callithamnion by the involucrate favellæ and by the disposition of the tetraspores. As we have Spermothamnion separated from Callithamnion in consequence of the absence of the gelatinous envelope found in true favellæ, so we have Bornetia separated in a similar way from Griffithsia. The genus can generally be recognized at sight by the rather large but very delicate cylindrical, oval, or, at times, globose cells, which do not bear immersion in fresh water even for a short time, and by the branching, which is dichotomous or a modification of the dichotomous type. The accurate specific determination from sterile specimens alone is generally impossible, so great is the resemblance of the fronds in the different species. The antheridia vary very much in the different species. In our only species they are sessile on the upper half of the globose terminal cells; in G. corallina they surround the nodes in tufts; and in G. setacea they are in dense approximate whorls, attached to the inner side of incurved branchlets. The tetraspores also vary in the different species. In G. Bornetiana and G. corallina they are in whorls at the nodes, and are attached to the inner side of short simple branches, which form a whorl around the node. In G. setacea the tetraspores occupy a position which corresponds to that of the antheridia. The favellæ are always truly involucrate and, as far as is known, terminal, in our species occupying the place of a suppressed dichotomy. The development of the procarp of C. corallina has been fully studied by Janczewski. In that species he found two trichogynes to each carpogenic system, as is also the case in the genus Ceramium. A nonsexual mode of propagation, by means of cells which give off root-like processes, has been described by Janczewski in G. corallina, and a similar process takes place in G. Bornetiana. G. BORNETIANA, Farlow. (G. corallina ? Harv., Ner. Am. Bor., Part II, p. 228, non Agardh.— G. globulifera, Kütz., Tab. Phyc., Vol. XII, Pl. 30.—G. globifera, J. Ag. in part.—G. Bornetiana, Proc. Am. Acad., 1877.) Exs.—Alg. Am. Bor., Farlow, Anderson & Eaton, No. 88. Fronds diœcious and dimorphous. MALE PLANT.—Globosely tufted, one to three inches high; filaments repeatedly dichotomous; lower cells cylindrical-obovoid, several times longer than broad, becoming shorter and broader above; terminal cells globose-pyriform; antheridia sessile, densely covering the upper half of terminal cell. Pl. X, Fig. 4. FEMALE PLANT.—Two to five inches high, loosely tufted, filaments repeatedly dichotomous; lower cells cylindrical-obovoid, becoming broadly pyriform above and then gradually diminishing in size toward the tip; favellæ solitary on the upper part of the superior cells; cells of involucre 10-20, unicellular, club-shaped, somewhat incurved. Pl. XI, Fig. 3. TETRASPORIC PLANT.—More slender than the female plant; tetraspores tripartite, densely clustered around the nodes of special branches; cells of involucre short and suberect. Pl. X, Fig. 5. On wharves, sponges, shells, and occasionally on Zostera.
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REPORT OF THE COMMISSIONER OF FISH
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