to root or fructification, they are found; though, in reference to the questions under discussion, accurate information on these points would be of considerable importance.
"That some mixture of other species probably exists may be inferred even from Dr. Meyen's statement, and indirectly from that of Lieut. Evans, who, in his communication published in Major Rennell's invaluable work on the Currents of the Atlantic, asserts that he found the Gulf-weed in fructification, which he compares with that of Ferns, a statement which would seem to prove merely that he had found along with the Gulf-weed a species of Sargassum with dotted leaves, the real fructification of the genus bearing [79 no resemblance to that of Ferns, though to persons slightly acquainted with the subject the arranged dots on the leaves might readily suggest the comparison.
"With regard to the non-existence of roots in the Gulf-weed as a proof of specific distinction, it is to be observed that the genus Sargassum, now consisting of about sixty species, is one of the most natural and most readily distinguished of the family Fucacæe, and that there is no reason to believe that any other species of the genus, even those most nearly related to, and some of which have been confounded with it, are originally destitute of roots; though some of them are not unfrequently found both in the fixed and in considerable masses in the floating state, retaining vitality and probably propagating themselves in the same manner (see Forskål, Fl. Ægypt.-Arab., p. 192, n. 52). It is true, indeed, that a Sargassum, in every other respect resembling Gulf-weed, has, I believe, not yet been found furnished either with roots or fructification, neither Sloane's nor Browne's evidence on this subject being satisfactory. But the shores of the Gulf of Florida have yet not been sufficiently examined to enable us absolutely to decide that that is not the original source of the plant; and the differcnces
- See Sloane's Jam. i, p. 59. I have examined Sloane's specimens in his Herbarium; they belong to Gulf-weed in its ordinary form, and are alike destitute of root and fructification; hence they are probably those gathered by him in the Atlantic, and not those which he says grew on the rocks on the shores of Jamaica. Browne's assertion to the same effect is probably merely adopted from Sloane.