336 PLANT LIFE. 



The Flora of these shale heaps has been given in 

 more detail, because many railway lines are composed 

 of clinkers, or some similar material, and it is not so 

 easy in the case of these embankments to distinguish 

 between the ordinary field weed-flora and that peculiar 

 to the cinder tracks. It will be seen, that not one of 

 the ordinary field weeds takes a leading part on the 

 shale. Persicaria, Spurrey, Chickweed, and Nettle are 

 generally not to be found upon them. 



The railway-track flora is, in Scotland, decidedly 

 different from that of the fields through which the rail- 

 way runs. Generally, as has been already shown, the 

 plants found upon the cinders are, especially at first, of 

 a more Southern affinity. The following are among the 

 most conspicuous : Hieracium aurantiacuin^ Tragopogon 

 porrifolius^ and Linaria minor. Anthyllis vulneraria and 

 Hieracium pilosella are also very characteristic of railway 

 banks in some places, as well as almost all the plants 

 quoted above for shale heaps. Many escapes and plants 

 unusual in the district are to be expected on railway 

 sidings, both from the character of the ground, and also 

 on account of the special facilities for travel, which are 

 afforded to the plants by the railway trucks coming 

 from all parts of the country. Very often, the embank- 

 ments and the cuttings show quite different floras. 



Another very characteristic flora seems to depend for 

 its existence on the waste nitrogeneous soil, to be found 

 near the dwellings of mankind. In the very centre of 

 the African continent one can determine with accuracy 

 the site of a former native village by the presence of 

 nettles. In Britain the common Nettle, Plantago Major, 

 Chickweed, Shepherd's Purse, Docks, Chenopodium, and 

 others, are the characteristic forms. Plantago major, the 

 ''White Man's Footsteps" of the Red Indian, owes its 



