STEVENSON— INTERRELATIONS OF FOSSIL FUELS. 481 



Grand'Eury presented to the Geological Congress a paper in 

 which he discussed elaborately the occurrence of various types of 

 plants. He regards the deposits as Stephanien. The paper in the 

 Guide gives more of detail respecting localization. 



The Upper Sterile stage passes upward into coarse conglomerate, 

 which Stur thought analogous to the Rothliegende of Rossitz; but 

 there is no unconformity. The Rothliegende flora is not abundant. 

 Cordaites and Pccopteris are present and Tceniopteris abnormis has 

 been found but no trace of CalUpteris has been observed. Walchia 

 pinniformis was seen in the St.-Chamond, but it does not continue 

 into the St.-£tienne stages. The Avaize (Middle St.-fitienne) con- 

 tains precursors of the Permian. 



The Productive Coal Measures show erect trees with their roots, 

 associated with well-preserved plant impressions, all indicating au- 

 tochthonous vegetation. Rooted trunks and stumps are uncovered 

 daily near St.-Etienne. His belief is that the trees, in every case, 

 grew in water with their roots penetrating the ground below. In 

 many cases, the stems have been removed during mining work but 

 usually the vegetable soil was not disturbed ; it is traversed by roots, 

 some herbaceous, some ligneous, which often pierce impressions of 

 leaves. Stigmaria is the most common form. These have their 

 roots spread out in normal position and frequently retain the delicate 

 appendages. They penetrate the underclay and are interlaced in it. 

 There are many other types, which he regards as even more satis- 

 factory. Chief among these is Calalnites, whose erect stems give 

 off rhizomes, which, in turn, give off rootlets ; all of the subterranean 

 organs are well preserved and are in normal position. Calamoden- 

 drons have their stems bound to the soil by a complete system of 

 roots. Psaronius stems are very numerous and are surrounded at 

 base by innumerable roots, pushed down obliquely into the soil. 

 When the plant, subjected to accumulation of alluvium, was obliged, 

 in order to live, to give off free roots in the water, these passed 

 downward and buried themselves in the soil below. Stumps of 

 Cordaites are equally numerous with their woody roots, divided 

 and subdivided even to rootlets, which have a comb-like arrange- 

 ment. Syringodendrons, with complete Stigmaria roots and rootlets 

 are of frequent occurrence. Fossil fruits are abundant. Roots of 



