CALAMITES 



239 



allowable to apply such a term to a group of plants 

 which, is now less complex in structure and fructifica- 

 tion, and has not anything like the stature of its extinct 

 ancestors. But, although the glory of the race has 

 departed, its existing remnants can evidently hold their 

 own, as the gardener who has to cope with the incursions 

 of Equisetum arvense has reason to know. We may say 

 of Equisetum limosum that it is breaking bounds. It 

 does not seem to be content that its kind should dwindle 



Pig. 75. — Stiqmaria ricoiDBS. 

 From coal-measures in Yorkshire. 



to extinction, but it is now on conquest bent. I have 

 observed within the last few years how it is invading 

 Highland tarn and Lowland pond, and becoming quite 

 dominant in marshy places. 



Fossil Horsetails are generally called " Calamites," 

 the name of the genus Calamites {calamus, a reed), 

 which was the most important of the Palaeozoic genera. 

 The investigation of their fossil remains has yielded a 

 considerable and almost complete mass of information 



