ROACHES AND OTHER ANCIENT INSECTS 



are to an abundance of hard-wood, leafy trees and shrubs, 

 and a multitude of flowering plants. None of these 

 forms of vegetation had yet appeared. 



Much of the undergrowth of the Carboniferous swamps 

 was composed of fernlike plants, many of which were, 

 indeed, true ferns, and perhaps the ancestors of our 

 modern brackens. Some of these ancient ferns grew to 

 a great size, and rose above the rest in treelike forms, at- 

 taining a height of sixty feet and more, to branch out 

 in a feathery crown of huge spreading fronds. Another 

 group of plants characteristic of the Carboniferous flora 

 comprised the seed ferns, so named because, while closely 

 resembling ferns in general appearance, they differed 

 from true ferns in that they bore seeds instead of spores. 

 The seed ferns were mostly small plants with delicate, 

 ornate leaves, and they have left no descendants to modern 

 times. 



Along with the numerous ferns and seed ferns in the 

 Carboniferous swamps, there were gigantic club mosses, 

 or lycopods, which, ascending to a height sometimes of 

 much more than a hundred feet, were the conspicuous big 

 trees in the forests of their day (Fig. 54). These lycopods 

 had long, cylindrical trunks covered with small scales 

 arranged in regular spiral rows. Some had thick branch- 

 ing limbs starting from the upper part of the trunk and 

 closely beset with stiff, sharp-pointed leaves; others 

 bore at the top of the trunk a great cluster of long slender 

 leaves, giving them somewhat the aspect of a gigantic 

 variety of our present-day yucca, or Spanish bayonet. 

 The bases of the larger trees expanded to a diameter of 

 three or four feet, and were supported on huge spreading 

 underground branches from which issued the roots — a 

 device, perhaps, that gave them an ample foundation in 

 the soft mud of the swamps in which they grew. 



The Carboniferous lycopods furnished most of our coal, 

 and then, in later times, their places were taken by other 

 types of vegetation. But their race is not yet extinct, 



[87] 



