A manual of the British Algae. Containing generic and specific descriptions of all the known British species of sea-weeds, and of conferae, both marine and fresh-water / By William Henry Harvey.

William H. Harvey

Date:: 1841

Credit: A manual of the British Algae. Containing generic and specific descriptions of all the known British species of sea-weeds, and of conferae, both marine and fresh-water / By William Henry Harvey. Source: Wellcome Collection.

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$into a roundish, gelatinous mass. Grev. — Named in honour of the Rev. M. J. Berkeley, an assiduous and accomplished British botanist, author of 6 Gleanings of British Alga] of the article 6 Fungi ’ in ‘ Hooker’s Biit. Flora,’ and of seve- ral admirable memoirs on the fructification, &c., of that ex- tensive class of plants. 1. B. fragilis, Grev. Grev. Crypt. FI. t. 294; Grev. in Hook. 1. c. p. 416; Ag. Consp. Crit. p. 24. Parasitical on Zostera and the smaller marine Algae. Appin, Capt. Car- michael. Near the Land’s End, Mr. Ralfs. — “ Plant of a reddish brown colour, and roundish or oval form, consisting of a rather firm gelatinous mass or receptacle, less than half an inch in diameter, and a number of filaments which seem to spring from its surface. This gelatinous receptacle is firmly attached to the plant on which it grows, sometimes surrounding the small branches of Furcellaria fastigiata. The filaments are immersed for half their length in the receptacle, the extremities being free. They are gela- tinous, exceedingly tender and fragile, simple, attenuated towards the apex, apparently destitute of external membrane, and containing a number of ob- long or rather fusiform frustules, arranged longitudinally, but without or- der.” Grev. Cr. FI. — Mr. Ralfs’ plant exactly agrees with a specimen in my possession from Capt. Carmichael. CXXVI. SCHIZONEMA. Ag. Frustula in longitudinal series or scattered, and inclosed within a simple or branched, gelatinous, mucous, or membra- naceous frond, composed of one or several tubes. — Name, to divide, and vY\y.a, a thread; the branches of the ty- pical species being formed, as it were, by cleaving the frond. * Fronds erect, branched, robust, (Schizonema). 1. S. obtusum, Grev.; frond robust, cartilagineo-gelatinous, elastic, firm, ultra-setaceous, laxly tufted, fastigiate, many times dichotomous ; axils rounded ; apices obtuse ; frustules minute, very numerous, oblong, binate. Grev. in Hook. 1. c. p. 413; Crypt. FI. t. 302. Parasitic on small Alg®, in the sea. Frith of Forth, Dr. Greville. Ap- pin, Capt. Carmichael. Torquay, Mrs. Griffiths. Salcombe, Mrs. Wyatt. Coast of Antrim, Mr. D. Moore.—Frond 2 or 3 inches high, robust, thicker than a hog’s bristle, and nearly of equal diameter throughout; laxly tufted, irregularly dichotomous; the lower divisions somewhat distant, the upper closer, frequently very close, in which case they are somewhat entangled. Substance firm and elastic. Colour yellowish green, not much changed in drying. Odour somewhat offensive. Frustules very minute, closely packed in a transparent jelly. A handsome and distinct species, well marked by the rounded axils and obtuse apices. Mrs. Griffiths finds it “dark brown” when recent; in other respects her specimens accord with the Scotch ones, and in a dry state their colour is identical. P$