304 Marine Algw of Berwick-on-Tweed. 



A very small form of this variety grows on the rocks near 

 high- water mark at the Singing Coves, and a little to the south- 

 ward of them. The fronds are very narrow, from an inch to two 

 inches and a half high, either simple or once or twice dichoto- 

 mously branched, the midrib distinct, the receptacles small and 

 very obtuse. In my Herbarium I have called this variety forma 

 nana, but I do not know whether it has already received a name. 



F. LATERIFRUCTA, GrCV. 



Scott. Crypt. Fl. vi., p. 319. 



" The lateral branches which bear the receptacles, narrow and 

 densely dich >tomously flabellate " Farlow, I.e., p. 100. 



Tnis variety, which is not uncommon on our coast, bears a 

 very close resemblance to Fucus ceranoides, but is much thicker 

 and more opaque. 



f. spiralis, Linn. 

 Sp. PI., p. 1159. 

 "Fronds short and spirally twisted" Farlow, I.e. 

 Common near the mouth of the Tweed. 



F. BALTIC A, J. A(). 



Spec. Alg. i., p. 210. 

 Sijn. Fucus vesiculosns, var. snbeeostatns, Ag., iSpec. Alg., p. 91. 



Fucus balticns, Ag., Swensk., Bot. torn. 8, tab. 516; Grev., Crypt. 

 Fl. t. 181 ; Harv., Phyc. Brit. Descr., pi. 204 ; Harv., Man. p. 18; 

 Ktz., Tab. Phyc. x., pi. 12; Gobi, Brauntange, p. 19, t. 2, fig. 

 19-22. 

 E.vsiec. Fucus vesiculosus, var. baltica, Cm., Alg. Finist., no. 105 ; 

 Desmaz., Bxsicc. 2nd Ser. 203 ; Aresch., Alg. Scand. Ser. nov. 1. 

 Hnb. Along the muddy banks of the Tweed above the railway bridge 



on the Tweedmouth side of the river. Local but abundant. 

 Fronds from one to three inches long, very narrow, irregularly 

 dichotomously branched, bladders wanting, midrib indistinct. 



A curious variety grows on the mud, amongst the roots 

 of Scirpus maritimus, and the rank grassy herbage along the 

 margin of the river at the Yarrow haugh, about three-quarters 

 of a mile above the railway bridge. Unlike most of the Fuci, 

 which are usually attached by scutate roots to rocks and stones 

 this variety invariably creeps along in the mud, the short stiff 

 fronds standing nearly erect, usuall}' closely packed together so 

 as to form indefinite patches which appear to be held in place 

 simply by the soft mud in which they grow. 



