of this genus (Biyol. Europ.), rely chiefly on the authority of Bridel in support of Barhda. But Bridel's authority is in favour- of Tortula, for lie adopted it in his earlier work. It was discontinued by him in 1819 (Mantissa) under the erroneous impression that the name had been legitimately given to a phenogamous genus ; whereas Barhda had been applied nine years before by Loureiro to designate a Chinese shrub. Hence Schrader, Sibthorpe, Swartz, Both, and all British writers on Mosses, retained Tortula, a name which would be at present unoccupied if not employed in conformity with the views of Hedwig and Schreber.
1. ToitTTjLA densifolia, Hook. fil. et Wils.; caule humili subdiviso, foliis patentibus confertis lanceolato-acuininatis acutis marginatis apice serratis sohdinerviis, theca oblonga, peristomii dentibus contortis, membrana basilari breviuscula, operculo subulato. (Tab. CLIII. fig. I.)
Hab. Falkland Islands, on clayey rocks near the sea at Port Louis, scarce.
Dioica? Caules 4-6 lin. longi, laxe caespitosi, subdivisi. Folia dense conferta, basi erecta, dein patentia stricta, lanceolato-subulata, acuta, subcarinata, rigidiuscula, margine cartilaginea vix incrassata, apice dentato-serrata, nervo valido rubello, lutescenti-viridia, areolis opacis minimis, basi majoribus subdiaphanis ; perichsetialia minora erecta. Seta 6-8 lin. longa, tortilis, fusca. Theca oblouga, erecta, fusca. Peristoma dentes basi membrana latius-cula conjuncti, rubelli. Operculum subulatum, capsula? longitudine. Calyptra dimidiata, fusca.
The only described species with which this can be compared is Barhda marginata, Bruch and Schimp. (Bryol. Europ.) ; but that is a smaller moss, having leaves not at all acuminated, and an excurrent nerve.
Plate CLIII. Tig. I. — 1, tuft of the natural size ; 2, leaf; 3, apex of ditto ; 4, thecse : — magnified.
2. Tortula robusta, Hook, et Grev.; caule elongato subramoso, foliis patulo-recurvis lanceolatis sub-carinatis acutis apice serratis solidinerviis, tlieca cylinclracea curvida, peristoma dentibus coutortis tubo ad tertiam partem producto, operculo subulato. T. robusta, Hook, et Grev. in Brewst. Ed. Journ. vol. i. p. 299. 1. 12. (Tab. CLIII. fig. II.)
Var. /3. foliis laxioribus viridibus.
Hab. Hermite Island, on sandy ground amongst grass at the head of St. Joachim's Bay, forming large patches. Var. /3. Falkland Islands, common in moist sandy places (barren).
Dioica, ceespitosa. Caules sesquiunciales, robusti, ramosiusculi. Folia lanceolata, vix acuminata, patentia, recurva, subcarinata, acuta, apice serrata, margine recurva, flavescentia, nervo tenui saturatius colorato percursa, siccitate erecta, incurva, subtortilia, areolis subrotundis, basi majoribus diaphanis, perichsetialia similia erecta. Seta uncialis, sinis-trorsum tortilis, rubella. Theca cylindracea, suberecta, curvula, rufo-fusca, ore rubello. AnnuVus persistens, albidus. Peristoma tubus basilaris dentium tertiam longitudinis partem sequans, albidus, dentes contorti, pidehre rubelli. Operculum subidatum capsula dimidio longius, flavescens. Calyptra dimidiata, castanea. From all the European Syntricldce this species is distinguished by the serrated leaves. In size and general aspect it is not unlike Barhda Mulleri, Br. and Schimp.
After careful examination of the original specimens of Tortula robusta and T. serrulata, we have reason to believe that one, if not both, of these mosses is the same species as our Antarctic plants, differing only in the narrow leaves; but they are in too imperfect a state to determine very satisfactorily. The figure of T. robusta represents the leaves much too widely spreading, and they are also serrulate at the apex, just as in T. serrulata.
Plate CLIII. Fig. I. — 1, plant of the natural size; 2, leaf; 3, theca; 4, apex of theca and peristome : — all magnified.
3. Tortula Mulleri. Barbula Mulleri, Bruch el Schimp. Bryol. Euro}), fasc. 13-15. p. 44. t. 28.
Hab. Falkland Islands, on sand-hills near the Lagoon at Uranie Bay.
