280 THE WONDERS OF VEGETATION. 



one knows our marsh-plants, horse-tails and other 

 reeds, consisting of a single stem, cylindrical, hollow, 

 worthless and uninteresting ; our lycopodiums or club- 

 mosses, our ferns, and all the host of modest, unsightly 

 cryptogams these are the descendants in modern 

 times of the plants of the era of the first coal forma- 

 tion. For the number of vegetable productions, 

 however, this period, the period of transition from the 

 primitive to the secondary epoch, is far superior to all 

 others ; and to this amazing fertility we owe the un- 

 measured extent of the valuable coal fields which are 

 to supply our race for ages in Europe and America. 

 Instead of rising to the height of only one foot, 

 these " horse-tails," etc., rose then to the height of 

 40 to 50 feet, and the degenerate club-moss (Lycopo- 

 dium), which now reaches rarely three feet, grew in 

 primitive ages to a height of 90 feet. In those 

 ancient forests club-mosses had the proportions of 

 stately trees. Mushrooms sometimes attained 40 feet 

 in diameter, and tree-ferns, such as shown in our illus- 

 tration, rose uniformly to a height of 30 feet at least. 

 But imagination would go greatly astray if it fancied 

 that in like manner our oaks measured then 200 feet, 

 our pines 400 feet, our elms 60 feet in diameter, etc. 

 " The young earth," says Zimmerman, " expended all 

 its strength in developing reeds and brakes, mosses and 

 mushrooms, and while we find mosses equal to trees, 

 and perhaps mushrooms as big as mountains, there 

 did not exist a single tree in those days larger than 

 those of our own times." 



But although at that period the whole surface of 



