STEVENSON— INTERRELATIONS OF THE FOSSIL FUELS. 131 



to the meter ; but occasionally the lignite is 30 to 60 centimeters 

 thick and is mined. Quartz masses are present in the lignite as well 

 as in the limestone, which, judging from Daubree's description, are 

 probably of secondary origin. This Lobsann fuel is the lignite bacil- 

 laire, the Nadelkohle, which is merely debris of palm trees, from 

 which connective tissue has been removed, leaving the loosened 

 bundles of fibers. This constitutes the greater part of the beds and 

 the arrangement shows that the stems w-ere prostrate. But with this 

 is another fibrous type, much finer and allied to mineral charcoal. 

 Microscopic examination proved that this is derived from coniferous 

 wood; palms and conifers were associated in the forests. Succinite 

 is abundant in this lignite, but the balls are rarely larger than a pea 

 and usually are of pinhead size; he counted 40 droplets in a cubic 

 decimeter. It is most common in beds consisting largely of conifer- 

 ous debris, the fibers of mineral charcoal being still impregnated with 

 the resin, as appears distinctly under the microscope. This lignite is 

 always laminated, the laminae being less than one millimeter thick 

 and alternately bright and dull, the latter being the less pure. Buli- 

 iiiits and Planorhis were obtained from the lignite. This freshwater 

 series of lignites and limestones is succeeded by marine marls, con- 

 taining Spatangiis, Cerithium, Vcnericardia and other forms of simi- 

 lar habit. 



Potonie^®- described the great deposit of brown coal near Senften- 

 berg in Niederlausitz. The bed is more than 10 meters thick, and is 

 mined by stripping at several places. The author gives reproduc- 

 tions of two photographs, one being a panorama of the principal 

 excavation, the other showing distribution of erect stumps. As in 

 many recent and Quaternary peat deposits, one finds here several 

 generations of forest, one above the other, embedded in humus 

 material, the only difference being that homogeneous peat has been 

 converted into brown coal. In the floor, as in the roof, are many 

 great erect stumps, those of the former being rooted in the under- 

 clay, those of the latter, in the brown coal. Some stumps have a 

 diameter of several meters and the intervals between trees are such 



182 H. Potonie, " Ueber Autochthonie von Carbonkohlen-Flutzen und des 

 Senftenberger Braunkohlen-Flotzes," Jahrb. d. k. prciiss. geol. Landesanst. f. 

 1^95, P- 97 ff- Citations from separate, pp. 19-24. 



