BROADHEAD — COAL MEASURES IN MISSOURI. 329 



capped with beds of bituminous shale. They include those 

 of Grand River as far as Utica, and those of Chariton 

 River. The sandy shales also occasionally contain seams 

 of coal of varying thickness and persistency. 



Group I. — This Group corresponds to Prof. Swallow's 

 "Lower Coal Series," and includes all the coal rocks beneath 

 those enumerated in the General Section. Not having the 

 proper facilities of connection, I have omitted them from 

 that section. Their thickness is 60 to 90 feet, and include 

 several important coal beds, namely, the coal of Boone, 

 Callaway, Audrain, Ralls, Monroe, the eastern part and 

 middle of Randolph, Macon and Adair. 



There are several thick beds of fire clay and bituminous 

 shale. The limestones are generally bluish-drab, thin- 

 bedded, impure, and contain but few fossils. Chonetes me- 

 soloba (Nor. & Prat.), Spirigera Maconensis (Sw.), Sp. Mis- 

 souriensis (Sw.), Sp. subtilita (Hall), Productus nuricatus 

 (Nor. & Prat.), Spirifer perplexus, Sp. cameratus (Mort.), 

 Sp. Kentuchensis (Shum.), Sp. hirsatus (Mort.), Chmtetes 

 milleporaceus, Fusulina cylindrica. In Randolph County 

 a Fucoid was obtained from calcareous sandstone very 

 closely resembling the Fucoides cauda-galli of the Che- 

 mung Group. It occurs a few feet beneath the 4' feet coal 

 bed. Fossil wood is often found in large masses, and I 

 suppose it to be derived from the sandstone of this Group. 



GENERAL REMARKS. 



Sandstone and Sandy Shales. — From inspection of the 

 Section it will be perceived that we have enumerated 754 

 feet of sandstone and s^ndy shales, or about ^ of the whole 

 mass. It is scarcely correct to separate the sandy shales 

 from the sandstone, since the one passes into the other 

 very suddenly and at short intervals. 



The sandstones and shales frequently contain small par- 

 ticles of silver mica, and are generally soft and more 

 or less ripple-marked. Some of the firmer beds of the upper 

 coal series make good grindstones. Beautiful examples of 

 cross lamination are sometimes seen. The Lamellibranchs 

 and Gasteropods are found in the upper series. Fossil 

 plants, including Calamites and Ferns, range throughout. 

 Sigillariee have been observed in the lower measures. 



Argillaceous Shale forms about 730 feet, \ of the whole 

 section. Its prevailing color is drab, sometimes blue, olive, 

 and green, rarely purple. The strata are generally thinly 

 laminated, sometimes micaceous, and pass insensibly into 

 sandy shale. They possess a jointed structure and usually 

 a smooth soapy feel. Concretions of carbonate of iron are 



