340 Mr. Weaver on Floetz Formations. [Nov. 



flinty slate, lydianstone, clayslate, jasper, quartz, sandstone, 

 limestone, calcareous ironstone, and iron ochre, with mica, and 

 iron pyrites ; not assembled all together in any one quarter, but 

 differently grouped in different districts. 



In the forest of Thuririgia, also, this formation is more nearly 

 allied to a siliceous than to a calcareous conglomerate ; and at 

 Ilmenau, it contains portions of hornstone porphyry of a flesh or 

 brownish-red colour ; while in the circle of Neustadt, the lowest 

 portion of the coarse conglomerate being ironshot and coloured 

 red, it has then a near resemblance to the rothe todtliegende ; 

 which circumstance has no doubt partly led to the confounding 

 of the two formations together. 



In Hesse, in the district of Riegelsdorf, the weissliegende con- 

 sists of a coarse calcareous conglomerate, a base of grey clay 

 marl enveloping rounded pieces of* quartz, micaslate, hornstone, 

 clayslate, jasper, felspar, and slaty clay marl, with scales of 

 white mica, single laminae of calcareous spar, and more rarely 

 rounded pieces of compact limestone. 



Generally speaking, the weissliegende, when partaking more 

 of the character of marl than of sandstone, is more or less iron- 

 shot, and coloured yellowish or brownish. 



To complete the distinctive characters of this formation, other 

 minerals, occasionally entering into its composition, must also be 

 noticed. Of these, calcareous spar is frequently found in dis- 

 seminated laminae, or collected in round masses, which are 

 usually hollow and lined with crystals ; granular and fibrous 

 gypsum, sometimes alternating with it in thin layers, and specu- 

 lar gypsum in lenticular portions. Heavy spar is more rare. 

 Mica is generally distributed. Grains of mineral pitch are found 

 in it immediately below the copper shale, in the Sangerhausen 

 district. Streaks and layers of pitch coal and slate coal, not 

 exceeding half an inch in thickness, and mineral charcoal in 

 angular pieces, several inches in circumference, have occurred 

 only in the Groscamsdorf district. 



In several tracts, the weissliegende is metalliferous for certain 

 distances, the upper layers being impregnated, one or more 

 inches in thickness, with metallic substances, principally ores of 

 copper ; but ores of cobalt have also appeared, beside iron 

 pyrites, galena, native bismuth, blende, and copper nickel. In 

 these cases, the copper shale commonly proves barren, but 

 in some places both are found rich in metal. 



The only instance of organic remains noticed in this formation 

 is that of chamites, found near Riegelsdorf, at a depth of several 

 fathoms below the copper shale. 



In many tracts, the weissliegende forms only a slight bed, but 

 in some quarters it becomes considerable, e. g. in the Riegelsdorf 

 district, where its thickness varies from 70 to 130 feet. 



The analogues of the weissliegende in England, are to be found 

 in the calcareous conglomerates, or popplestones, of Devon, and 



