THE SPHENOPHYLLS 



241 



size of an average modern species, lie will be able to 

 form some sort of a mental picture of the peculiar cast 

 which the Calamites would 

 give to the Palaeozoic land- 

 scape. Since the halcyon 

 days of the Calamites, which 

 were in greatest abundance in 

 the Carboniferous Period, the 

 Equisetales as a group have 

 gradually dwindled in size 

 and importance, and we know 

 from the few existing species 

 how extensive the falling off 

 has been. The group has 

 displayed a tenacity which 

 commands our respect, and 

 one cannot avoid admiration 

 for a race which has sur- 

 vived the chances and vaga- 

 ries of many aeons, and whose 

 existing forms are the repre- 

 sentatives of an aristocratic ^_. 

 ancestry. 



A glance at the Spheno- 

 phyllales will terminate our 

 review of the chief Palaeozoic 

 plant groups. In the absence 

 of the researches of palaeo- 

 botanists, we should cer- 

 tainly have had no knowledge of the Sphenophylls. 

 They seem to have arisen and become extinct in the 



31 



Fig. 76. — Arch^ocalamites ra- 

 diatus. Branch with Leaves 

 in Whorls ; Leaves with re- 

 peated Two - Forked Divi- 

 sions. 



