4G 



FOSSIL ESTHERIyE. 



Formation,' published full particulars as to the occurrence of the so-called Posidonia 

 minuta in certain beds of the Trias. 



The Triassic striata of the Wiirtemberg district he grouped thus : 



Keuper 1 



(900-1000 feet.) 



Muschelkalk 



(700—1 030 feet) 



'Keuper-Sandstein, or variegated marls with sandstone. (Including the so-called 



bone-bed of the Lias.) 

 Keuper-Gyps, or variegated marls with gypsum. (Including a Reptiliferous 

 breccia.) 



/Gypsum. 

 Limestone. 

 Dolomite (50 feet). 



Lettenkohlengruppe 



/ Sandstone. 

 Marl-slate {Estherid). 

 Lettenkoble 2 (1 — 12 inches). 

 „ Shale and sandstone {Estheria). 



{Limestone of Friedrichshall (150 — 400 feet). 

 Anhydrite-group (350—400 feet). 

 Wellenkalk (200—240 feet). 



Bunter Sandstein (600—800 feet). 



At pp. 114, 119, and 120, of Alberti's 'Monographic,' he says — "Above the dolomite of the Muschel- 

 kalk, and below the Lettenkohle (Coal-shale), are clay-beds and shales, which pass more or less into 

 sandy shale, and sometimes into sandstone, and then they become very micaceous. In these strata occur 

 Equisetum arenaceum, Bronn, Tceniopteris vittata, var. major, Brougn., and Fucoidal bodies ; also Reptilian 

 remains (Mastodonsaurus), Gyrolepis tenuistriatus, Ag., Hybodus sublcevis, Ag., and Posidonia minuta, 

 Goldfuss. 



" P. minuta, Gold/., is square-oval, with 9 or 10 concentric ribs, of the size of a flax-seed ; like 

 P. Becheri (Bronn) from the Grauwacke, and the P. Bronni (Goldf.) of the Lias, but smaller and thinner. 

 It is figured in Von Ziethen's ' Verst. Wiirt.,' pi. 54, fig. 5. It occurs at the Primthal, 3 near Rottweil 

 (about fifty miles south of Stuttgart), in the Bore-hole No. 3, near Schweninger" 



1 A detailed section of the Keuper, as seen near Stuttgart, is given in the 'Silurian System,' p. 30 ; 

 and a careful comparison of the English German, and French Triassic beds will be found iu the same 

 chapter. 



2 In his ' Steinkohlenformation in Sachsen,' p. 4, Geinitz says — "The Lettenkohle (Shale-coal or 

 Keuper-coal) is described by Voigt, in his ' Versuche einer Geschichte der Steinkohlen, der Brannkohlcn 

 und des Torfes,' as the generally impure, argillaceous, and pyritous coal-beds of the Keuper, lying on the 

 Muschelkalk, and met with on the Schbsserberg, near Mattstedt in the Grand-Duchy of Weimar, and at 

 some other places in Thuringia, in France, in Saxony, on the bank of the Main, near Schweinfurt in Swabia, 

 and in Lothringen. It is of little value as a fuel, even for lime-burning and furnaces, and is chiefly used for 

 the manufacture of alum and vitriol. The organic remains of the Lettenkohle-group have been described in 

 a monograph by J. G. Bornemann, in 1856." 



s A specimen from the valley of the Prim is referred to above (p. 44), as having been kindly pre- 

 sented to me of late by the veteran geologist Von Alberti. 



