Phascum, Hedw.

Maier, Eva & Price, Michelle J., 2014, Georg Bojung “ Scato ” Lantzius-Beninga and his contributions on the anatomy of moss capsules: a transliteration from the original German texts, Boissiera 67, pp. 1-79 : 30-32

PHASCUM .

The lower and the central part of the capsule of Phascum show a construction that is found in all mosses, with exception of the previously described Sphagnum .

During the growth the cell tissue of the capsule separates into two components, an outer and an inner one, in the way that the three or four inner cell layers are torn off from the other inner layers, but remain connected at the apex of the capsule and below at its base, and also partly by confervoid filaments, thus forming the structure of the so-called “outer capsule membrane” (Tab. LVI. Fig. 2 . me).

[original page 567] In the column-shaped part, situated on the inside, again two different groups of cells are observable: the outer four cells, the mother cells followed by the spore surrounding layer – the spore sac ( Fig. 2 . sc)*) – and the inner, mostly composed of tissue of big cells – the columella ( Fig. 2 . cc). Between the latter named groups of cells appears here, as in most of the mosses, no special gap; as we will see later on, as this is the case in some species of Polytrichum only.

In the upper and lower parts of the capsule where the columella passes through the capsule point and the seta, the tissue becomes denser and the cells smaller ( Fig. 2 . csp and cin), and in this region the membrane of the mature capsule is brown.

The structure of the point itself shows nothing exceptional, no trace of the development of an annulus or a peristome.

The capsule of Phascum patens , as well as that of Phascum cuspidatum , is of the same structure.

[original page 568]

Note. In Phascum also I could observe the development of the spores; it is the same process as in Gymnostomum ( pyriforme ) and Funaria ( hygrometrica ): from only one layer of mother cells develop two other mother cells from which the spores originate.

There are few other mosses, their cell tissue being so clearly transparent as in Phascum , that make easier the observation of the cell development, and the cutting of the very small capsules into sufficiently thin sections. I saw most clearly in a mother cell with a completely preserved membrane, two younger cells, likewise with distinct membranes, enclosing each of the four separated small cells: the young spores.

Figures

Fig. 2. Part of a transverse section of a capsule of the same moss. Meaning of the letters and magnifiction as for the previous figure.