IOWA ACADEMY OP SCIENCES. 91 



in which the formations of the Missouri river were colored as 

 New Red sandstone, or Triassic. The English edition of the 

 map, which accompanies his "Geology of North America," 

 has the same coloration. 



Two years later, Hayden* gave out the results of his obser- 

 vations along the Missouri river, and refers the rocks south of 

 the Platte to the Carboniferous or coal measures. 



From observations made during a brief visit to the Missouri 

 river region in Nebraska, by Marcouf and Capellini, thePlatts- 

 mouth beds were placed in the lower Dyas or Permian. A year 

 afterwards. Meek J pointed out, in a special paper, the fact 

 that the rocks in question belonged to the coal measures, and not 

 to any younger formations. Geinitz,§ who described the fos- 

 sils collected by Marcou in Nebraska, only incidentally 

 mentions the limestone at Plattsmouth, remarking that it was 

 probably below the Nebraska City sections, and belonged to 

 the " Oberen Kolenkalk, " or the upper part of the lower Car- 

 boniferous series. 



Up to this time, although many references had been made 

 to the formation, no specific designation had been given to the 

 limestone. Meek appears to be the first to attempt to call it 

 by a geographic name. He refers! about 200 feet of strata 

 below the first heavy limestone above the Plattsmouth to the 

 "Platte division." This included all of the shales now 

 known to be not more than 100 feet thick in the vicinity of the 

 Platte river, the limestone now called the Plattsmouth, and 

 the few feet of shales beneath exposed at the landing. As the 

 major part of "division" is a well defined formation com- 

 prised almost entirely of shales, the term Platte has been 

 reserved for that subdivision. Meek,l however, in the same 

 memoir referred to, terms the fossiliferous limestones which 

 comprise most of his section as the "Plattsmouth beds. " By 

 this name they have since become widely known. For this 

 reason it is believed that the limestone should be continued to 

 be known by the name of a locality which has become classical 

 in American geology. 



* Proc. Philadelphia Aead. Nat. Sci., Vol. IX, p. 110, 1857. 

 T Bull. Soc. G6ol. France, 2e s6rle, t. XXI, p. 137, 1864. 



* Am. Jour. Scl., (2), Vol. XXXIX, p. le."), 1865. 



§ Memoirs, d. d. Leop. Carol. Akad. Nat., 1866, 91 pp. 

 II U. 8. Geol. Sur. Nebraska, p. 85, 1872. 

 T Ibid., p. 94. 



