Organography of plants, especially of the archegoniatae and spermaphyta . THE SPOROGONIUM IN HEPATICAE a water-reservoir. The sterile cells are distinguished by their starch-content, whilst the fertile ones contain more proteid, a difference whichappears also in Aneura. The fertile cells are the larger and the dis-position of the two kinds of cells is such that at first groups of two to threesporocytes with a few sterile cells attached to them are formed. The fluidwhich fills the inside of the spore-capsule renders possible perhaps anexchange of material, for soluble materials may pass into it
Organography of plants, especially of the archegoniatae and spermaphyta . THE SPOROGONIUM IN HEPATICAE a water-reservoir. The sterile cells are distinguished by their starch-content, whilst the fertile ones contain more proteid, a difference whichappears also in Aneura. The fertile cells are the larger and the dis-position of the two kinds of cells is such that at first groups of two to threesporocytes with a few sterile cells attached to them are formed. The fluidwhich fills the inside of the spore-capsule renders possible perhaps anexchange of material, for soluble materials may pass into it from the sterilecells and be again taken out of it into the fertile cells. At any rate thefertile cells are here chiefly nourished by the chlorophyllous sterile ones andby the chlorophyllous wall of the capsule ; the short stalk of the sporogoniumdisappears so soon that the sporogonium has from an early period to dependupon itself for its nourishment. The division of the nuclei in the sterilecells ^ recalls rather the nuclear fragmentation of the tapctal cells in the. ?x->^^ Fig. 84. Sphaerocarpus terrestris. /, three spore-tetrads and two sterile cells from a ripe , longitudinal section through a sporogonium about half-developed, the sporocytes are not yet divided;c, calyptra ; P, perianth. anthers than the divisions within the sporocytes. The spores remain intetrads (Fig. 84, /); the sterile cells are still visible when the spores are ripe. The method by which the spores are set free, whether by rotting ofthe sporangial wall or otherwise, is unknown in Riella and Sphaerocarpus,as well as in Corsinia. Probably in them all the spores float away afterthe sporogonium has withered. In Corsinia the sterile cells, as in Sphaero-carpus, are still living at the time of the ripening of the spores, and are pro-vided with small chloroplasts ; they also serve as nutritive cells, but areexternally much more like elaters than are those in Sphaerocarpus. (B) The sterile cel
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