36 MOSSES AND LIVERWORTS 



a comparison of figs. 15 and 16 of Plate IV. with 

 fig. 17 of the same plate, the former representing 

 some of the leaves taken from the stem and 

 branches of the Common Rough-stalked Feather- 

 moss (Brachythecium rutabulum) frequently to 

 he met with in the country, growing in bright, 

 glossy green patches on banks, walls, trees, etc. 

 while the latter gives one of the leaves of which 

 the flower is formed. In some cases, however, 

 the variation in form between the two kinds of 

 leaf is very slight, as shown in figs. 18 and 19 

 of Plate IV., which give leaves (the former one 

 of the ordinary leaves of the plant, the latter 

 one from a flower) belonging to a very common 

 moss (Camptothecium sericeum), the pale yellow, 

 silky sprays of which often form conspicuous 

 objects on walls, roots of trees, and banks by the 

 roadside. 



These large leaves doubtless serve a very real 

 purpose in the life of the plant, as they must 

 help to retain small drops of rain or dew round 

 the reproductive organs enclosed in them, and 

 thereby aid, as we shall presently see, in the 

 fertilisation of the latter. 



After removing several layers of these leaves, 

 we shall come upon a quantity of loose cellular 

 substance, which, when examined with a fairly 

 strong lens in the microscope, is seen to consist 

 of numerous very small bodies of a peculiar form ; 

 these are the Organs of Reproduction. There 



