FOSSIL BOTANY. 2S9 



spinous or acicular leaves, and terminated by scale-cones, 

 "which bore spores like the Club-Mosses. The Sigillarim 

 were likewise arboreous, but their trunks exhibit longi- 

 tudinal ribbing or fluting, and vertical rows of seal-like 

 impressions representing the leaf arrangement; they were 

 but little, if at all, branched, and clothed with numerous 

 long, tapering leaves. 



4. The Conifers were represented by the genus Protax- 

 ites, allied to the Yew (Taxiis). 



203. The Flora of the Carboniferous Age, or the 

 vegetation of the Coal-measures, is of peculiar interest, 

 both because of its great abundance and because of its 

 diversity of forms. About one-fourth of all known fossil 

 plants are from the Coal-measures. There were many 

 marine plants, among which may be mentioned the curious 

 Spiral-plant, or Spiropliyton. Fungi existed at that time. 

 But the great majority of plants may be referred to the 

 groups Equisetinee, Filices, Lycopodinse, and Coniferse. 



1. Equisetinae. Besides plants of the genus Calamites, 

 which has already been described, there were representa- 

 tives of other closely-related genera, as Aster ophylUles, 

 Sphenophyllum, etc., all of which became extinct in the last 

 period of the Carboniferous Age. 



2. The Ferns were abundantly represented — nearly 

 one-half of all the plants of the Coal-measures belong to 

 this order. Some of them had creeping stems like our 

 common Ferns, and others were Tree-Ferns, such as are to- 

 day found growing only in warm latitudes. A Trec-Fern 

 of the Coal-measures, called Megaphyton, had its large 

 fronds in two vertical ranks; other common genera were 

 Cyclopieris, Odontopteris (Fig 344), Neuropteris, etc., whose 

 leaflets, or pinnse, were destitute of a midrib; Sphenopteris, 

 Hymenophyllites, etc., whose pinnse had a midrib discern- 



