562 TRANS. OF THE ACAD. OP SCIENCE. 



Cherbourg; Mem. T. x., 2e Ser., T. i., from the Society. Academie 

 Imp. dee Sciences de St. Petersbourg: Mem. T. ix., T. x.,Nos. 1-2; Bull. 

 T. ix., from the Academy. K. Akad. der "Wissensehaften zu Berlin: 

 Monatsb. Jalirg., 1845, from the Academy. Soci^te" Vaudoise des Sci- 

 ences Nat: Bull., vol. ix., No. 54, from the Society. Authorship of 

 Shakespeare, by Nathaniel Holmes, New York, 1866, from the Author. 



Hon. N. Holmes read the following communication from 

 Prof. Jules Marcou, of Paris, France, on the Dyas in Nebras- 

 ka, as follows: 



[translation.] 



The Dyas commences upon the right bank of the Missouri river, five 

 miles below Aspinwall and the mouth of the Little Nemaha river, in the 

 northeast corner of the county of Richardson. It penetrates the State of 

 Missouri precisely at the mouth of the Nishnabatona river, and forms a 

 part of Atchison county, and thence enters into the State of Iowa, where 

 it appears to form a large band which extends to St. Mary, opposite the 

 mouth of the Platte river. 



In Nebraska, the Dyassic rocks form the right bank of the Missouri 

 river from Aspinwall to Plattesmouth and Aureopolis, that is to say, all 

 the bluffs of the counties of Nemaha, Otoe, and Cass. They repose in 

 discordance of stratification upon the Carboniferous formation, the rocks of 

 which dip to the wast northwest at an angle of 4 degrees, whilst the rocks 

 of the Dyas incline generally to the south southwest at an angle of 5 or 

 6 degrees. Elsewhere the Dyas is found in a little basin with a very 

 Blight anticlinal line, which passes between Brownsville and Aspinwall. 



The rocks of the Dvas differ a good deal from those of the Carbonifer- 

 ous upon which they repose. They consist of clays of red, green, and 

 grey color, i.e. variegated; of whitish, grey, and yellowish limestones; 

 of dolomites and yellow and grey sandstones. 



The best section of the Dyas of Nebraska, and the most easy to be 

 studied, is that formed by the bluff at the Nebraska City landing, at Otoe 

 City, at Peru, and at Brownsville, where the strata are higher in the 

 Dyassic series than at Nebraska City ; whilst at Rock Bluff, Plattesmouth, 

 and Aureopolis, on the contrary, we find the lower layers forming the 

 base of the Nebraska Dyas. 



In the section of Nebraska City may be seen all the details, layer by 

 layer, beginning at the base at the level of the river. It is proper to re- 

 mark that the section was taken in the month of October, when the 

 waters of the river were so low that navigation was interrupted. 



SECTION AT THE LANDING OF NEBRASKA CITY. 



A. a. Red clay with sandstone slab of red and grey colors. ) 

 a»' Green clay with nodular limestone, containing Produc- I 



tus Koninckianus Vera, and Spirifer cameratus Morton. | 

 a H - Fossiliferous limestone with Schizodus Rossicus Vern., y 8 ft. 



Productus Koninckianus Vern., and Chonetes muc.ro- 



nata M. & H. 

 a iH - Grey clay, unfosiliferous. 



B. b. First crinoidal limestone with Orthis crenistria Phill., 



Slenopora columnaris Sclilot., Dyadocrinus injlexus Gem. 

 b>- Green clay with Spirifer cameratus Mort., Chonetes mucro- 



nata M. & H., Stenopora columnaris Schlot. 

 b H - Blond limestone, fossiliferous. 

 l)Hi. Green clay, 

 b'f- Blond limestone, fossiliferous, with Productus punctatus }■ 11 ft. 



Mort., and Orthis crenistria Phill. 

 b v - Green clay. 

 b vi - Limestone. 



b Til > Black clay with a coal seam 2 to 4 inches thick, 

 bviii. Second crinoidal limestone with Stenopora columnaris 



Schlot. J 



