234 PLANT-LIFE 



seems to owe its preservation to the reverence in which 

 it has long been held by the Chinese and Japanese. So 

 far as we can learn from the record of the rocks, the 

 Cordaitales first appeared in Devonian times. They 

 seem to have reached their greatest abundance in the 

 Carboniferous Period; towards the end of that Period 

 they began to dwindle, becoming fewer in the Permian 

 Age, and going out of existence in Early Mesozoic times. 



Our brief account of the Palaeozoic flora would be 

 incomplete without reference to three other groups of 

 considerable importance — the Lycopodiales, Spheno- 

 phyllales, and Equisetales, all spore-bearing plants. 



Modern Lycopods have already been described 

 (p. 161). In Palaeozoic times there was a plant, a 

 genuine Lycopod, to which the name Miadesmia has been 

 given; its petrified remains have been found in coal- 

 balls. Miadesmia was somewhat like Selaginella 

 (p. 163), but it produced something approaching to a 

 seed, and, if it be correct to class it with the Selaginel- 

 lacese, it certainly attained a more advanced condition 

 than has been noted in any of its successors. Very little 

 has been discovered concerning the geological history of 

 the homosporous Lycopodiacese (p. 162), but the hetero- 

 sporous Selaginellaceae have been traced as far back as 

 the Carboniferous Period. Our living Club-Mosses are 

 but humble representatives of Lycopods, some of which, 

 in Palaeozoic times, flourished as big trees in quite royal 

 dignity, and must have been a marked feature of the 

 ancient landscape. The genus Lepidodendron, whose 

 fossil remains are so abundant in Carboniferous rocks, 

 embraced Lycopods, some of which attained great size. 



