IV. ECTOCARPACEiE.— Sphacelaria. 137 



1. Sphacelaria cirrhosa, Ag. ; stems naked at the base, short, densely tufted, 

 simple or branched, pinnate or bipinnate ; pinna? opposite, alternate or irregular, 

 simple ; spores globose, scattered, sessile or shortly stalked. J. Ag. Sp. Alg. l,p. 

 34. Kiitz. Sp. Alg. p. 464. Harv. Phyc. Brit. t. 178. Conf. pinnata, E. Bot. t. 

 2330, (right hand fig.) 



Hab. On the small Alga3 between tide-marks. Long Island Sound, Captain 

 Pike. Ship Ann Point, Con. Messrs. Walters, Hooper, and Congdon. New Bedford, 

 Mass. Mr. Congdon. 



Fronds forming globose, fastigiate tufts, an inch or rather more in diameter ; more 

 or less densely tufted, scarcely fastigiate, and only a quarter inch in height. Filaments 

 capillary, of equal diameter throughout, straight, once or twice pinnated, the pinnae 

 very irregular ; in some specimens closely set, opposite and plume-like, in others 

 distant, altei'nate, variable in length on the same branch ; either erecto-patent or 

 spreading horizontally, simple, naked, blunt. The spores are not uncommon, and 

 are found scattered along the pinnee. Colour a foxy brown or olive. Substance 

 rigid, scarcely adhering to paper in drying. 



Probably common on the shores of the Northern and Midland States. Numerous 

 specimens that I have received are very similar to European forms of this variable 

 plant. 



2. Sphacelaria radieans, Dillw. ; filaments decumbent, sending out fibrous radi- 

 cles in the lower part, with a few irregular, simple, straight, naked branches ; 

 spores clustered, sessile. Harv. Phyc. Brit. t. 189- S. olivacea, J. Ag. Sp. Alg. 

 vol. 1, p. 30. S. radieans and S. olivacea, Kiitz. Sp. Alg. pp. 463, 466. Conf. 

 olivacea, E. Bot. t. 2172 ; and C. radieans, t. 2138. 



Hab. On sand-covered rocks, between tide-marks. (I gathered on rocks at 

 Beverley, on Boston Bay, what I supposed to be this species ; but have mislaid my 

 specimens. W. H. H.). 



A small plant, forming spreading patches half an inch in height, and two inches 

 or more in diameter. The specific name radieans, though not adopted by Prof 

 Agardh in his recent work, has evidently the claim of priority, having appeared in 

 English Botany 34 plates earlier than the rival name olivacea — a name moreover, 

 equally applicable to any other species of the genus, all being olive-coloured. 



VOL. ni. ART. 4. 



