Handbook of British Hepaticae : containing descriptions and figures of the indigenous species of Marchantia, Jungermannia, Riccia and Anthoceros . allysolitary, but more usually radiating, overlapping,and forming imbricated tufts. In rare instancesthe upper surface of the frond is punctate withminute pores, which are the analogues of stomatain the higher plants. The foliaceous Hepatics have a thin thread-likestem, which is so weak that the plants are onlyerect when growing in dense tufts, or mixed withSphagnum or other mosses, the lower portion beingmostly naked or only furnished with radicles
Handbook of British Hepaticae : containing descriptions and figures of the indigenous species of Marchantia, Jungermannia, Riccia and Anthoceros . allysolitary, but more usually radiating, overlapping,and forming imbricated tufts. In rare instancesthe upper surface of the frond is punctate withminute pores, which are the analogues of stomatain the higher plants. The foliaceous Hepatics have a thin thread-likestem, which is so weak that the plants are onlyerect when growing in dense tufts, or mixed withSphagnum or other mosses, the lower portion beingmostly naked or only furnished with the stem is forked or branched, and thebranches themselves sometimes pinnate ; occasion-ally it is normally simple. The stems being sooften prostrate the arrangement of the leaves is intwo rows, on opposite sides of the stem, but in-serted more or less obliquely, so as to lie nearlyflat, in prostrate forms (fig. 2). The leaves are ex-ceedingly variable in outline, seldom so simple as inmosses, and without any mid-rib or nerve. In INTRODUCTION many cases they consist of two unequal lobes,folded together face to face, with the margin. 2. either entire or toothed. The arrangement ofleaves on the stem may be succubous, or disposedin a spiral which turns from left to right, sothat the anterior border of each inferior leafis covered by the posterior border of that im-mediately above Or the arrangement may beincubous, in which case the spiral turns fromright to left, and the anterior border of eachinferior leaf covers the posterior border of the leafplaced immediately above it. If one of these stems is examinedcarefully onboth sides witha lens, it will beobserved that4_ 6 theydiffermuch in appearance, and especially that the under, or ven-tral, surface exhibits a series of smaller leaves, some-handbookofbritis00cookuoft
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Keywords: ., bookauthorcookemcm, bookcentury1800, bookdecade1890, bookyear1894
