10 THE DEVONIAN OF MISSOURI. 



this place it is a calcareous sandstone, whilst at another point, 

 only a short distance along the same outcrop, it passes into 

 layers of arenaceous limestone, containing its usual fossils, and 

 alternating with beds of obliquely-laminated sandstone. It 

 also occurs in the bed of a small branch of Little Splice creek, 

 some mile and a quarter south of the above locality, where it is 

 more calcareous, and contains many fossils, of a few species. 



On the north side of the Moniteau, it was again seen at Mr. 

 William Routon's place, in Sec. 27, Town. 46, R. 14. Here is 

 only exposed about eight feet at the base of a hill, and it is made 

 up of course, partly-rounded grains of quartz, cemented with 

 calcareous matter. 



The only organic remains seen in this part of the group were 

 Terebratula reticularis, an Orthis like 0. resupinata, a plicated 

 Spirifer rather under medium size, and a small smooth Spirifer." 



Meek failed to differentiate between Callaway and Cooper 

 and nearly or quite all the arenaceous rock belongs to the former. 



In his discussion of the geology of Marion County in the 

 same report Swallow 1 says of the Cooper there: "This marble is 

 easily distinguished by its lithological characters. It is a hard, 

 compact, blue limestone, which has disseminated through it, 

 numerous small angular masses of pellucid calcareous spar. 

 These particles of spar often present the appearance of Arabic 

 characters, like the quartz in graphic granite. The marble is 

 hard and durable, and receives a fine polish. 



It passes down into a light-colored, thin-bedded, argillaceous 

 limestone which is, probably, the upper part of the Hudson 

 River Group. A single filiform coral, Acervularia Davidsoni? is 

 the only fossil found in the rock." 



Acervularia Davidsoni Edwards and Haime was not found 

 by the writer, but it occurs in the Callaway about ten miles south 

 of Swallow's locality. 



In Meek's report on Saline County, published in 1873, 2 he 

 described the Cooper as follows: "The exact position of this 

 rock in the series has not been determined as no organic remains 

 have yet been found in it, and it has only been seen in connec- 

 tion with the Chouteau Limestone and the Saccharoidal Sand- 

 stone. That is to say, it has been seen immediately beneath 

 the former and reposing upon the latter. In this county it was 

 only observed associated with the Chouteau Limestone, as 



^eol. Surv. Mo., Reports I and II, p. 178. 

 •Geol. Surv. Mo., 1855-1871, p. 176. 



