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These were of three kinds, which were shown under the microscopes on 

 the table. In one case the whole substance of the cell stands up like a little 

 cushion ; these are termed pulvinate or cushioned. Another kind has the 

 cuticle of the cell rising up and taking the form of conical papillae ; while 

 the third was the verruciform, or wart-like papilla. These are all very 

 characteristic of various families ; thus the verruciform papillae are seen in 

 E/icalypta, and it belongs no doubt to the Toi-tulacece, or screw mosses, 

 which have this kind of cell. 



A nerve may be present, or none at all, and there may be two, or even 

 three or four. The nerve may have several layers of cells, and extend half- 

 way up the leaf, or to the point, and often it is longer than the leaf, and 

 appears as a hair, which forms long white points to the leaves, and gives 

 them a hoary aspect. 



The margin of the leaf may be perfectly smooth or entire, or serrated, or 

 thickened, or bordered with cells of other forms. 



All these features were most important, because the specific character 

 depended in most cases upon the leaves, and he laid great stress upon 

 their microscopic structure. This was so far more important than the 

 size and colour of the plant, because it had absolute definite structure im. 

 pressed upon it from its first formation. 



Then as to the reproductive system, the modes in which the plants con- 

 tinued their kind. 



The mosses are termed cryptogams, so named by Linnaeus. But the 

 mode by which the impregnation of mosses is accomplished is not concealed* 

 but simple, and easily traced. They have distinct male and female organs, 

 which are termed antheridia in the male, and archegonia in the female. In 

 the family of the Polytrichaceae the antheridia appear as beautiful little 

 sausage-shaped bodies in separate rosettes, or clusters of leaves, usually 

 differing from the stem leaves and termed bracts. In flowering plants the 

 floral leaf is termed a bract, and he did not see why the same term should 

 not be applied to mosses. In some cases the male and female organs are 

 on separate parts of the plants, and in other cases the male organs are on 

 one plant and the female on another. In this way there are formed three 

 groups, which are termed Synoicous where the sexual organs were found 

 together in one inflorescence, Monoicous where the male and female are on 

 separate parts of the same plant, and Bioicous where the male and female 

 organs are found on separate plants. 



Around this inflorescence there is usually found a beautiful cluster of long 

 threads termed paraphyses. These have been usually considered abortive 

 antheridia, but their purpose no doubt is to maintain moisture round these 

 organs. It will be found, even in dry weather that fluid mucous matter is 

 always present ; in his mind the object is to maintain the vitality of the 

 antheridia. 



The archegonia are more like a flask with a long neck, and they also have 

 paraphyses round them. As time goes on the little top bursts, and it is 

 found that a long channel has been formed down the centre to the dilated 

 base, which always contains a large central cell. The antheridium also 



