Page:The Botany of the Antarctic Voyage.djvu/145

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Campbell's Islands.]
FLORA ANTARCTICA.
123

It is With much reluctance that we refuse to adopt the views of Bruch and Schimper, who, in their beautiful 'Bryologia Europaea,' subdivide Splaclinum into three or four genera. The several characters which the two species here enumerated possess and which are not conformable with those of any of the subgenera alluded to, would, were these adopted, oblige us to construct a fifth for their reception. S. octoblepkarum and S.purpurascens are so nearly allied to the S. mnioides, that we doubt the propriety of even retaining two genera which might be founded on the very dissimilar structure of the calyptra, but on that character alone, unaccompanied with any ditference of habit. In one of Bruch and Schimper's divisions, Tetraptodon, the calyptra is truly dimidiate and neither indexed nor appendiculate at the base ; in the other, we always find it, previous to its separation from the vaginula, indexed at the base, but when the seta elongates and carries up the calyptra, this inflexed portion is drawn out and remains as a lacerated and somewhat incurved membrane or appendage. A similar structure is observable in Sc/ilotJieimia, under which genus the development of S. quadrifida is illustrated.

In all the species which we have had an opportunity of examining in a recent state, and especially in S. spliericum, ampullaceum and mnioides, there is a very peculiar arrangement of the sporules, in lines radiating from the columella. Each of these lines is composed of eight or more sporules, contained either in separate cells or in membranous tubes, of a nature evidently analogous to the asci of some Fungi. This structure is probably common to all the species and may be traced obscurely in the dried state of some ; it has, however, escaped the observation of Bruch and Schimper, who perhaps did not examine specimens in a sufficiently young state.

The southern species, those at least from the higher latitudes, inhabit decayed vegetable matter.

1. SpLAcmajM purpurascens, Hook. fil. et "Wils. ; caule elongato, foliis patulis obovatis acurninatis integerrinris vmdulatis evauidinerviis apicibus recurvis, theca elliptico-oblonga microstoma, apophysi obconica angusta, operculo conico. (Tab. LVII. Fig. V. 1.) Far. ft minor. (Tab. LVII. Fig. Y. 8.)

Hab. Campbell's Island; in moist bogs, amongst grass; altitude 1000 feet.

Caides laxe caespitosi, vix ramosi, semiunciales et idtra. Folia patula, subremota, planiuscula v. undulata, siccitate crispa, laxe reticulata, inferiora luride purpuraseentia. Infiorescentia monoica; flores masculi gemmaceo-capitulifomies ad baseos foliorum sessiles v. in ramulis propriis terminales. Seta uncialis, valida, rubra, nitida, sensim in apophysin theca brevioreni incrassata. Peristoma denies oeto, conniventes, luteoli, integri v. medio rima longitudinali ad apicem non producta fissi, siccitate fusci et reflexi. Columella apice dilatata, plerumque breviter exserta. Operculum paivum, anguste conicum, subrostellatum, rarius hemisphericum, flavescens v. rufo-brunneum. Calyptra non visa.

Nearly allied to S. octohlepharum, but larger, the leaves wider, more distant, less produced at the apex and more crisped when dry. Capsule narrow and more attenuated below, with a smaller mouth. In the var. /3, both the two lateral of the longitudinal and the transverse lines on the teeth are very faint; in no instance do the teeth in this species appear to be really formed of four, the lateral lines always ceasing below the apex ; the lower part of each double tooth is formed by four cells in a line, but their summits of only two.

Plate LVII. Fig. V. — 1, 8. purpurascens, of the natural $i;e; 2, a leaf; 3 and 4, capsides ; 5, teeth closely approximated in pairs ; 6, the same, of var. ; 7, the same of var. a, with a longitudinal fissure and some sporules : — magnified. 8, a small tuft of var. /3, of the natural si:e.

2. Splachntjm octoblepliarum, Hook. ; subramosum, foliis obovatis longe acivminatis subpiliferis integermnis, theca una cum apophysi clavata, peristomii dentibus octo solitariis. S. octoblepliarum, Rook. Muse. Exot. t. 167. Schwaeg. Suppl. II. pt. 1. p. 105. t. 129. (omitted in B ridel. Bryol. Univ.)

Var. /3, pyr /forme; foliis magis erectis confertis, apophysi angustiore. (Tab. LVII. Fig. TV. 1.)