LIST OF ILLUSTRATIONS 
Page 
Plate I: 23 
Figure i. A coal ball from Southern Indiana, contain¬ 
ing a fossil seed (Trigonocarpus). Natural size. 
Figure 2. A section of a small stem out of a coal ball, 
showing the woody fibres. Magnified 75 times. 
Plate II: 37 
Branch of a Gingho, showing fan-shaped leaves. 
From Missouri Botanical Garden, St. Louis. One- 
tenth natural size. 
Plate III: 53 
Impressions of fossil ferns and fern allies from the 
Pennsylvanian. Natural size. 
Figure 1. A fern leaf (Sphenopteris). 
Figure 2. A fern leaf (Neuropteris). 
Figure 3. A fern leaf (Pecopteris). 
Figure 4. A branch of a horsetail (Calamites). 
Plate IV: 65 
Devonian landscape reconstructed in New Yor\ State 
Museum, Albany. 
Plate V: S3 
Landscape of Pennsylvanian age (after Potonie). 
Plate VI: 93 
Landscape of Triassic age, reconstructed in Stuttgart. 
Plate VII: HI 
Cycad tree (after Chamberlain). 
Plate VIII: 121 
Cross section through an oil field. 
