THE SMITHSONIAN INSTITUTION. 113 



Ptilota plumosa is also a plant of this region, tlie only species (as far 

 as I know) that is met with in Long Island Sound being P. sericea, 

 Gm. Bhodomehe are more abundant here than in the Sound, but are 

 not limited to this division; Odonthalia {a, peculiarly nothern form) 

 has been seen only at Ilaliflix. Dmnontia ramentacea, so abundant at 

 Iceland, is found also at Newfoundland, and near Halifax, where I 

 gathered it plentifully. Of this plant I possess a single specimen, 

 picked up by Miss Frothingham on Rye Beach, New Hampshire. All 

 the species I have mentioned are Arctic forms confined in the European 

 waters to very high latitudes, and all appear to vegetate nearly as far 

 south as Cape Cod, to which limits they are almost all confined. The 

 Marine flora of this region as a whole bears a resemblance to that of 

 the shores of Iceland, Norway, Scotland, and the North and North 

 West of Ireland. 



2d. Long Island Sound, including under this head New York har- 

 bor and the sands of New Jersey. 



The natural limit of this region on the south is probably Cape Hat- 

 teras, but after passing New York the almost unbroken line of sand is 

 nearly destitute of Alga3. I have not received any collection of sea 

 23lants made between Long Branch and Wilmington. In comparing 

 the plants of the sound with those of our 1st region, a very marked 

 diiference is at once seen. We lose the Arctic forms, Agarum, Ehod. 

 cristcda, Odonthalia, Dumontia i-ameniacea, and Ptilota plumosa, whose 

 place is supplied by Sargassum, of which genus two species are found 

 at Greenport and at other points in the Sound ; by various beautiful 

 Callithamnia and Polysiplionia'-; and by abundance oi Delesseria Ameri- 

 cana and Dasya elegans. Those two latter plants are not limited to 

 this region, but are greatly more abundant here than north of Cape 

 Cod. I)el. Americana seems almost to carpet the harbor of Green- 

 port, and is equally abundant in various points in the Sound, and 

 Dasya elegans grows to an enormous size in New York harbor, and 

 is plentiful throughout the region. Seirospora Griffithsiana is not 

 uncommon; it grows luxuriantly at New Bedford, whence Dr. Roche 

 has sent me many beautiful specimens of it, and of other Ceramiece. 

 Pihahdonia Bailey i, Gracilaria midtipartita, (narrow varieties) Cliry- 

 symenla divaricata and C. Rosea arc also characteristic forms. Dele^- 

 seria Leprieurii, found in the Hudson at West Point, scarcely belongs 

 to this region, but is a tropical form at its utmost limit of northern 

 distribution. 



3d. Cape Hatteras to Cape Florida. Of the Alg^ characterizing 

 this region we know little except those found in the neighborhood of 

 Charleston, and a few specimens collected at Wilmington, N. C., and 

 at Anastasia Island. Many species found within these limits are 

 common to the second region ; others are here met with for the first 

 time. Of these the most remarkable are Artlirocladia villosa and a 

 Nitopliyllum, found at Wilmington; a noble Grateloupia, probably 

 new {G. Gibbesii, MS.) found at Sullivan's Island, and Delesseria 

 Jiypoglossum, already mentioned as occurring at Charleston and Anas- 

 tasia Island. I have seen no Fucoid plant from this region; but if 

 there were a suitable locality, we ought here to have Sargassa. None 

 grow at Sullivan's Island, where Grateloupia Gibbesii is the largest 



