list of the sea-weeds or maeine alg^e, etc. 285 



Sporochnace^e. 



5. Desmarestia aculeaia, Lam. Common at Gay Head, Nantucket, 



(Miss Mitchell.) 



6. D. viridis, Lam. Orient Point, Long Island. June, 1871. 



Laminariace^e. 



7. Laminaria saccharina, Lam. Yery common at Gay Head and Mon- 



tauk, Long Island ; Wood's Hole, Orient Point, Newport. 



S. L. digitata, Lam. Gay Head, Montauk. Probably the southern- 

 most habitat of this species. 

 L. trilaminata, Olney. In August, 1870, 1 picked up on the north 

 beach, Orient Point, a fragment much decayed, which, at the 

 time, I thought belonged to this species. Professor Gray having 

 mentioned that he had seen, several years ago, at Gay Head, a 

 plant which might possibly have been this species, I visited that 

 spot several times, but found no trace of L. trilaminata, although 

 there was abundance of L. saccharina. The specimens, supposed 

 to have been L. trilaminata, were probably nothing more than a 

 monstrous form of L. saccharina. This view is strengthened by 

 the fact that I have seen, at Mount Desert, Agarum Turneri with 

 three aire; and I have seen two specimens of L. saccharina, in 

 which one edge of the frond had become thickened like a cord, 

 and at the apex the cord was beginning to split into two layers, 

 at right angles to the frond itself. 



9. Chorda filum, Stack. Very common in shallow water. 



10. C. lomentaria, Lyngb. Orient Point. June, 1871. 



DlCTYOTACEJE. 



11. Stilophora rhizodes, J. Ag. Waquoit. A few specimens floating 



near Wood's Hole, in July ; near Providence, (S. T. Olney.) No- 

 where common. I have lately seen a specimen sent from Lenor- 

 mand to Dr. Hillebrand, marked SiUophora Lyngbyei, Ac New 

 York Bay. By some this species is considered a variety of the 

 last named. 



12. Dictyosiphon fceniculaceus, Grev. . A few specimens floating off 



Naushon. 



13. Punctaria tenuissima, Grev. Dredged in three or four fathoms. 



Wood's Hole. Common at Orient Point. June, 1871, 



14. P. pkmtaginea, Grev. With the latter, and equally common at 



Orient Point. 



Chordariaceje. 



15. Chordaria flagelliformis, AG. Nobska, Gay Head. Not so abun- 



dant as farther north. 



