94 LAMINARIACEiE. — Laminaeia. rv. 



Hab. Floating near Narragansett Pier, R. I. Mr. Olney. (v.' s.) 



I introduce this undesciibed and scarcely known plant, because it has already 

 obtained publicity in Mr. Olney's list of Rhode Island plants, quoted above ; but I 

 am unable to give a satisfactory description from the few fragments that have 

 reached me ; and probably, after all, these may belong to some strangely anomalous 

 form of L. saccharina. The fragments sent me by Mr. Olney and Professor Bailey 

 are labelled as part of a large Alga resembling L. saccharina in appearance, but 

 having a trilaminate frond ; that is, from the centre of the lamina, along its 

 whole (?) length, there projects a wing or additional lamina, making, with the two 

 halves of the true leaf, a third lamina. Nothing is known of the stipes. 



7. Laminaiiia digitata,ljam.. ; stem robust, woody, terete below, compressed above, 

 expanding into a leathery, oblong, or ovate frond, which is deeply cleft into many 

 linear segments of irregular breadth. J. Ag. /Sp. Alg. vol. 1, ^. 134. Harv. Phyc. 

 Brit. t. 223, and t. 338. Hafgygia digitata, Kiltz. Sp. Alg. p. 577- Phyc. Gen. 

 t. 30, 31. Fucus digitatus, L. Turn. Hist. t. 162. E. Bot. t. 2274. 



Hab. On rocks, at and below low-water mark. Common as far south as Cape 

 Cod. Narragansett Pier, R. I., Mr. Olney. (floating only), (v. v.) 



Boot formed of many stout branching holdfasts united together in a conical 

 mass. Stipe from two to six feet long, cylindrical below, from a quarter inch to an 

 inch in diameter at base, solid, tapering, and becoming compressed upwards, and 

 terminating in the base of a standard-like broad lamina. Lamina from one to five 

 feet long, or more, from one to three feet wide, deeply cleft from the apex to near 

 the base into many linear strap-shaped segments of uncertain breadth. Substance 

 of the stem woody, but flexible, horny when dry ; of the lamina leathery. Colour 

 olive, becoming dark in age. 



Possibly more than one species is here confounded. Some varieties, like that 

 figured in Phyc. Brit. t. 338, are very narrow, with very much compressed, or even 

 flattened stipes, and of a dark blackish-brown colour and glossy surface. Others, 

 which I have from Boston Bay, have dried extremely pale, and though I have not 

 seen perfect specimens of these, I remember to have noticed on the beach near 

 Nahant some forms of pale colour and with very flat stems, which may belong to 

 a peculiar species. The limits of species among these gigantic Alg£e can rarely be 

 determined from Herbarium specimens alone, and should be fixed by persons 

 familiar with the plants in their places of growth, and who have watched the 

 development of the frond through all its stages. 



