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development of the little green cellular body found within the pistil- 

 lidium which becomes the capsule of Marchantia polymorpha, and 

 states that from the facts observed and from analogy he is inclined to 

 believe that the young capsule is at first formed of a continuous 

 cellular substance, and that the cells of this tissue become parent- 

 cells, producing new cells within them, which they set free by 

 becoming dissolved, exactly as occurs in the production of the parent- 

 cells of the pollen-grains in the continuous cellular tissue of anthers. 

 M. Mirbel does not appear to have examined the contents of the 

 capsules until this complete separation of the cells had taken place, 

 when he describes them as consisting of minute elongated cells (the 

 young elaters) mingled with small squarish cells (the spores). But 

 Mr. Henfrey found the younger capsules to contain elongated cells 

 alone, and those of two sizes. The whole cavity was filled by such 

 cells apparently radiating from th'e centre ; the narrower cells being 

 interposed between much longer and broader cells of the same form. 

 The former were the young elaters, the latter the parent-cells of the 

 spores. 



The young elaters Mr. Henfrey describes as elongated slender 

 tubes attenuated towards each extremity, and filled at first with an 

 almost colourless coagulable protoplasm. After a short time starch 

 globules are seen within them, which might readily be mistaken for 

 the rudiments of the spiral fibre ; but the author believes that the 

 accounts given by some writers of the formation of spiral fibre in 

 spiral vessels from rows of minute granules are incorrect, and have 

 arisen from observation of starch granules lying in rows often running 

 obliquely across the tubes. After a greater enlargement in the length 

 than in the diameter of these cells the starch granules and finally the 

 protoplasm disappear, and faint streaks denoting the nascent fibres 

 are at length visible upon the walls. These gradually become more 

 and more distinct, until in the mature elaters they present themselves 

 in the form of strong flattened bands. In Marchantia there are two 

 fibres, the ends of which are confluent at the extremities of the tubes 

 in which they are contained; so that more properly speaking there is 

 but one endless fibre twisted upon itself, which may be represented 

 by a piece of string doubled with its ends united, and twisted spirally 

 upon itself. This is evidently the best possible condition of structure 

 for its purpose of acting as a spring. In unrolling, the fibre tears up 

 the membrane of the walls of the tube, which after the elaters have 

 been discharged is often no longer to be detected. 



While the elaters are passing through these stages the larger 



