258 Tracks of Animals in Variegated Sandstone. 



distinctly embedded upon the lower red sandstone, and in the 

 Saal valley, between Weissenfels and Diirrenberg, they are cov- 

 ered by the upper red clay. We find traces of track-casts also at 

 Crossen, at Weissenfels, and at Gross-Aga not far from Zeitz ; 

 however, only here and there, and perhaps less distinctly than at 

 Polzig, At the latter place, the animals seem to have congrega- 

 ted in herds. But however rare they appear in the other places, 

 the wide extent of the region in circumstances favorable to their 

 hardening, is worthy of attention. 



The quarries of Polzig and Klein-Porthen are situated in paral- 

 lel level vallies, and are separated from one another by a mountain 

 ridge about an hundred feet high and one mile broad. The ar- 

 rangement of the individual strata in them is represented on the 

 plate, (B,) and needs only a few explanations in addition. 



In both places, the sequence of the strata is tolerably uniform, 

 although some variations exist with respect to thickness and in- 

 ternal composition. The track-strata, indicated by arrows, may 

 be regarded as parallel, since their position in general corresponds 

 so exactly, that they might be held as actually identical. 



The lowest track-layer in both places occurs in a minutely gran- 

 ular gray-yellow sandstone, whose strata, from one to two feet 

 thick, and separated by a thin layer of clay, are preferably em- 

 ployed for the getting out of the larger building-stones, and on 

 this account, they are called by the workmen, " Werkbank."* 



Upon this follows, at Porthen, a firm, dark gray oolite, passing 

 beneaih into gray sandstone with traces of copper-green, but at 

 Polzig on the contrary, a firm, gray sandstone, which only rarely 

 contains oolite. At both of these places these strata are called, 

 on account of their hardness, " Eisenstein," and are used especi- 

 ally for road making. 



Next, at Porthen, greenish-gray slate clay, called " Schiefer- 

 schutt," and the same at Polzig, but alternating above and below 

 with sandstone strata. 



On this follows, at both places, the upper track-layer, on the 

 under surface of the sandstone strata, which, at Porthen, are thin, 

 and frequently alternating with slate-clay, on which account they 



* The local terms employed by the workmen I have not thought it necessary 

 t'j translate in the text or plate. I give their literal signification Werkbank, shop- 

 hoard or work-bench ; eisenstein, i/owsfone; sc\\\efex&chu\X, slate earth ; schalstein- 

 banke, shale-banks ; rother schult, red, earth ; sandplatten, sandplates. — Tr. 



