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The Museum Gazette 



to a large extent, that the different mosses are classified and 

 named. 



The tubes or pipes of which, as we have seen, mosses are 

 destitute, are minute, open channels which, in all the higher 

 vegetables, pass up from root to bud and through which the 

 sap ascends. Their cut ends can easily be seen in the surface 

 of any chip of young wood. The cell structure, which is all 

 that mosses possess, is to be recognised only by the aid of 

 a microscope. The railway foot warmer, if its handles were 

 taken away, or a soda-water flask without its neck, might serve 

 as good representatives of a moss-cell. We have to imagine 

 countless millions of microscopic flasks placed end to end and 

 resting side by side, and we have the structure of a moss leaf. 

 It must be remembered that these cells in the moss are living, 

 and that every one is quietly engaged in its own proper work. 

 Their walls are, however, not absolutely water-tight, and 

 they have plugholes like those of the foot warmer. Fluids 

 are constantly passing from one cell to another, or to the 

 external air. It is thus that the moss makes up for its want 

 of sap-tubes and keeps up a sort of circulation. It will 

 shrivel in hot weather and plump out in wet, and, above 

 all, it can, like other plants, prepare sap and supply it to the 

 buds which are wishful to grow. Here let us note that all 

 mosses are coloured, and that in all, some of their cells possess 

 the green colouring matter called chlorophyl, which has the 

 property of changing, under the influence of light, water and 

 its constituents into a nutritious sap. Mosses are no lovers 

 of sun, but a certain share of it is essential to their enjoy- 

 ment and their growth. In this they differ greatly from their 

 very distant relations, the fungals, which thrive in darkness. 

 As Mr. Woodhouse liked his gruel "thin, but not too thin," so 

 mosses like to have shade, but not too much of it. They are 

 found flourishing best on the shady sides of trees, rocks or 

 walls, and although some of them love bogs, but few grow 

 in streams or ponds. They are types of moderation and 

 humility, and they are patient opportunists, allowing them- 



