340 AI.GJE CONFERVOIDE.E. [Calithamnion. 



less regularly pinnated with shorter joints ; but the two extremes may be 

 traced into each other. The favellcE of this species are involucrated, 

 pedicellated, and precisely resemble those of a Griffithsia; but the 

 habit and affinities are like Calithamnion. 



5. C. Pluma, Ag. (feather?/ Calithamnion); filaments 

 creeping, stems erect subsimple naked below, the upper half 

 oppositely pinnate, pinna? erect appressed, articulations of the 

 stem 2 — 4 times longer than broad. — Ag. Sp. Alg. v. 2. p. 162. 

 — Conferva Pluma, Dillw. Conf Syn. p. 72. t. F. 



On the stems of Laminaria digitata, common ; first observed by the 

 late Miss Hutchins at Bantry.— Capsules similar to those of C Turneri. 



B. Hamuli alternate, pinnated or dichotomous. 



a. Secondary branches pinnated or plumulate. 



* Main-stems inarticulate. 



6. C. Arbuscula, Lyngb. (shrubby Calithamnion); stems 

 naked below robust cartilaginous, main branches papillose with 

 short imbricato-plumulatebranchlets, ultimate pinnules divaricat- 

 ed subsimple attenuate acute, capsules lining the inner faces of the 

 pinnules. — Lyngb. Hydroph. Dan. t. 38. /. 1, 2, 3, (excl. fig. 

 4, 5, 6.) — Conferva Arbuscuki, R. Broun. — Dillw. Conf. t. 85. 

 (not t. G.) — E. Bot. t. 1916? — Dasya Arbuscula and spongiosa, 



Ag. Sp. Alg. v. 2. p. 121 Asperocaidon Arbusc, Grev. Fl. Crypt. 



Edin.p. 307. 



On rocks and stones, in the sea. Abundant on the west of Ireland 

 and Scotland. Very rare on the east of Scotland. Firth of Forth, 

 Messrs. Grevdle and Arnott. — Stems subsolitary, as thick as a small quill, 

 destitute of branches and densely pilose in the lower part: 4 — 8 inches 

 high. Lesser branches thickly clothed on all sides with minute imbricated 

 plumules. Colour a fine claret. Capsules spheerical, sessile, with a 

 broad limbus. Favellce roundish -ovate, or irregularly lobed, mostly in 

 pairs. The figure in E. Bot. is not very characteristic. 



7. C. Brodicei, Harv. MSS. (Brodie s Calithamnion); stem 

 subopaque spuriously articulated slender, branches laxly set 

 with short elliptical quadrifarious plumules, ultimate pinnules 

 spreading obtuse subsimple, capsules roundish sessile on the 

 ramuli mostly solitary. — C. purpuraseens? Brodie MSS. 



On Algae, at Forres, Mr. Brodie. Coast of Northumberland, Mr. 

 Robertson. Torquay, Mrs. Griffiths and Miss Cutler.— 1—3 inches high, 

 cartilaginous, thrice as thick as hog's bristle at the base, gradually atten- 

 uated, tufted ; branches quadrifarious. Plumides 1—2 lines long, ellipti- 

 cal, rounded at the top, pinnae scarcely tapered, very obtuse, simple or 

 subramulose near the apex, erecto-patent. Colour pale brownish-red. 

 Main-stem inarticulated, longitudinally striated, branches subopaque with 

 obscure articulations, twice as long as broad, articulations of the ramuli 

 rather shorter. Capsxdes alternate or opposite, seated near the top of 

 the pinnules. Favellce sometimes produced on the same frond, or even 

 the same branch as the capsules. Such is Brodie's plant. Mrs 

 Griffiths sends us some beautiful individuals from Torquay, which, though 



