Objects for the Microscope. 33 



Before I describe the growth of a moss or the slides 

 before us, it is necessary to learn the several parts of its 

 fructification, arid, if possible, to procure specimens of each 

 of them. 



A moss is a flowerless plant ; the fruit or seed-vessel is 

 the only visible organ of reproduction, and consists of 



The capsule, or urn-like body, which contains the spores. 



The operculum, or lid of the capsule, which shuts in the 

 spores until they require light and air. 



The calyptra, or veil, which protects the young capsule. 



The peristome of the capsule, which in most of the mosses 

 is set round with a single or double row of teeth, such as 

 you see in Dicranum or Bryum, and which are curiously 

 regular in their number, varying from four to sixty-four, 

 but always a multiple of four. Remark this in any you 

 may examine ; there will be four or eight, sixteen or thirty- 

 two, and one variety (Polytrichum) has sixty-four; but 

 there will be no odd number. 



The inner peristome, or cilia, a fringe of delicate inner 

 teeth, often rising like a cone in the centre of the capsule, 

 pale yellow, or pure white, whereas the outer row is usually 

 crimson or brown. 



The columella is a column in the middle of the capsule, 

 round which the spores cluster, and which you will only see 

 by carefully dividing an unripe capsule lengthwise, making 

 a thin section, and looking at it with a drop of water under 

 a low power, when it will delight you. 



The growth of a little moss is so interesting that we shall 

 do well to watch it in our winter walks, from November to 

 April. 



Botanists are not yet quite agreed about the green 

 filaments, which are the first appearance of fructification, 

 and whose different cells contain the germs of the future 

 moss. They are called antheridia and pistillidia, analogous 

 to the stamens and pistils of a flower, but very different 

 in their structure and action. Read the chapter on the 

 structure and reproduction of moss in ' Carpenter on the 

 Microscope ' ; or, better still, read Hooker and Taylor's 

 ' Muscologia Britannica.' 



