Sphagnum C.Linnaeus 1753

I examined capsules of Sphagnum obtusifolium and acutifolium. They show a very simple structure: in their centre is an obtuse, conical columella that does not reach the culminating point (Tab. LVI. Fig. 1. cc) and around it is the space in which the spores develop (Fig. 1. ss). This space is present in all other mosses which I have had the opportunity to examine: initially at the beginning of the spore development, it is surrounded by a layer formed of relatively small cells, densely filled with chlorophyll (Fig. 1 sc); to this layer, outwardly below the superficial membrane, only three more cell layers are added, of which the nearest to the superficial membrane consists of cells filled with chlorophyll. The superficial cells themselves are empty of granulose contents and the membrane, mainly orientated towards the outer side of the capsule, is thickened.

A distinction between outer and inner membranes of the capsule, therefore, cannot be perceived.

At the place where, at the maturity of the spores, the operculum detaches, a slight depres- sion is visible (Fig. 1. a), and the superficial cells are markedly smaller than elsewhere in the capsule; otherwise nothing indicates a special development of an annulus.

Against the lower part of the capsule, especially in the inner of the apophysis-like swelling, the cells are somewhat elongate.

Note. In the month of May this year (1846) I was lucky to collect young capsules of the cited mosses where I could observe the spore development, and immediately I was convinced that it happens in the same way as I saw it in the past in other mosses (see my dissertation: De evolutione sporidiorum in capsulis muscorum. Gott. 1844. 4.). In the younger capsules I [original page 566] found a dense tissue of mother cells containing thick nuclei, in the older ones, at the same place, the mother cells had four already completely developed spores. As it is said, at the end of the filiforme cells should be formed, by constriction, the four spores, but I could not see anything. (Meyen: Neues System der Pflanzenphysiologie, Bd. III. p. 389). *)