Hab. Hermite Island, Cape Horn ; dredged up from about six fathom water, and on rocks at low-water mark, very rare ; Falkland Islands, Mrs. Capl. Sulivan.
Species pulcherrima, habitu Bonnemaisonia asparagoidls. Frons 2-4 imc. longa, cireumscriptione late ovata> 2 una lata, rigida, distiehe ramosa, v. ramosissiiua, ramis setaceis decomposito-pinuatis. Caitlis primarius simpliciusculus, basi inartioulatus, superne articulatus, tvi-striatus, compressus v. angulatus. Rami minores ramulis alternis ornati, omnes breves, subulati, e singulo serie cellularum formati, bine monosiphonii. Articuli omnes breves, caulini e tubis quatuor masqualibus (quorum 2 lateralibus latioribus,) circa cavitatem ceutralem dispositis conflati ; articuli ramulorum Callitliamnio forma et structura simUlimi. Ceramidia secus ramulos disposita. Color pulchre purpureo-roseus.
A very beautiful and rare species: distinct from any of its European and exotic congeners that have been described. Mrs. Sulivan's specimens are much finer and more branched than those from Cape Horn.
2 7 . STICTOSIPHONI A, Harv.
Frons purpurea, filiformis, cylindracea, ramosa, tubulosa, extus stictis quadratis notata, intus diaphragmatibus septata. Peripheries e cellulis quadratis tubum ceutralem cavum radiatim cingentibus formata. Ceramidia ? Stichidia aictoata, ramidos terminantifl, tetrasporas pluriseriatas foventia. — Algcepnsilla, caspitosee, e fills repentibus ortce, rupes marinas Antillanas, Austro-Atlanticas, Autarcticasque vise demersas v. ad limitem pleni maris osstus sitas incolentes. — Geuus Bostrycldce , Mont, valde afline.
A very natural little group : composed of a few species, which occupy the same position with regard to the high-water mark in the Southern Ocean, that Lichina and Catenella do in the Northern. As a genus it differs from Bostryckia, Mont., only in the more simple internal structure of the frond, aud broad, apparently septate, tubes, surrounded by only one row of cells occupying the centre of the frond : in habit aud other respects they are so closely allied, that it is doubtful whether Stictosiphonia should not rather be regarded as a subgenus of Bostrychia. The structure of the frond is very similar to that of Polysiphonia, differing chiefly in the cellules of the periphery being very short ; whilst those constituting the axis are lengthened.
1. Stictosiphonia Hookeri, Harv.; caulibus indivisis curvatis apice involutis, ramis lateralibus abbreviates alternis subquadrifariis erecto-patentibus, iuferioribus subulatis simplicibus furcatisve, superioribus alteine multifidis, ramulis subulatis acutis erectis, axillis acutis, stictis subtriseriatis, sticliidiis lanceolatis acutis ramulos minores terminantibus. Bostrychia Hookeri, Harvey in Lond. Journ. Bol. vol. iv. p. 269. (Tab. CLXXXVI. Fig. II.)
Hab. Hermite Island, Cape Horn; and the Falkland Islands : on rocks close to high-water mark; abundant.
Frons 1— una longa, dense csespitosa, rigida, atro-purpurea. Caulis plerumque simplex, per totam lougitudinem ramulis brevibus lateralibus ornatus. Rami nuuc omnes 1 lin. longi et indivisi v. superiores elongati 2-4 lin. longi, repetitim ramosi. Ramuli ultinii subulati, erecti erecto-patentesve. Rami ramulique omnes apicibus plerumque arete involutis : — chartae laxe adhseret.
A beautiful little plant, marked all over, under the microscope, with three rows of dark purple dot-like cells.
Plate CLXXXVI. Fig, II. — 1, plant of the natural size ; 2, stem, &c. ; 3, ramulus and stichidium ; 4, portion of stem ; 5, longitudinal and 6, horizontal section of ditto ; 7, tetraspores : — all magnified.
2. Stictosiphonia fastigiata, Hook. fil. et Harv. ; caulibus fastigiatis multifidis apicibus involutis,
