STEVENSON— INTERRELATIONS OF FOSSIL FUELS. 437 



same seam at different localities. Evidently there was localization 

 of contemporaneous floras. 



The upper coal group, above the Hochwald porphyry, has 80 

 seams of coal, 2 inches to 6 feet thick, but only 3 or 4 are workable, 

 as partings are numerous. There are two subgroups, separated by 

 a barren interval. 



In the lower subgroup, he found resin by no means rare in seam 

 I ; seams 4, 5 and 11 are caking; seam 6 has Sandkohle and seam 9 

 consists of Sinterkohle. Four has many thin layers of mineral 

 charcoal ; 1 1 is divided in distinct benches by partings of that mate- 

 rial ; but 5 has very little of it. The mineral charcoal is derived 

 from Araucarites wood. Stigmaria is present in the coal at one 

 mine; the upper bench of another seam contains Sigillaria, Sage- 

 naria and Stigmaria. The southward prolongation of one seam has 

 an abundant flora, which differs materially from that found in the 

 northern prolongation. 



The upper subgroup has 19 coal seams and the dip is 18° to 20°. 

 The coal contains Sigillaria, Sagenaria, Lepidophloios and much 

 mineral charcoal, the last in fragments up to 6 inches long. Resin 

 is in the coal of a mine near Waldenburg. Erect stems of Sagenaria 

 are in the roof of seam 9 and petrified wood was seen in a sandstone 

 quarry. At the Sophien mines, the coal shows Stigmaria and Sage- 

 naria on the surfaces of splitting; in the same neighborhood, another 

 . seam rests on clay, crowded with Stigmaria and its roof holds an 

 abundant and varied flora. At the Fund mine in Charlottenbrun- 

 nen, the roof of a seam is a compact, fine-grained sandstone, in 

 which he saw great prostrate stems of Lepidodendron and Sigillaria, 

 40 feet long and 30 inches in diameter. The floor has abundant 

 Stigmaria and occasional Calamites. Many Stigmaria with some 

 Lepidodendron, Calamites and Noeggerathia were seen in coal at 

 the Segen-Gottes mine. The flora of this sub-group is most abun- 

 dant, where the coal is thickest, but many types are confined to very 

 restricted areas. 



Similar conditions prevail in the Neurode district, where the 

 higher deposits are reached. Near Buchau he saw in sandstone, 

 several clumps of Araucarites stems, all apparently prostrate. Near 



PROC. AMER. PHIL. SOC, VOL. LIX, BB, DEC. 21, I92O. 



