560 PAL.EONTOLOGICAL REPORT OF GEOLOGICAL SURVEY. 



part of the state from (1,400) fourteen hundred to (1,500) fifteen 

 hundred feet. 



The thin veins above No. 12, are not wanting in distinctive organic 

 remains, and collections had already been made from some of these 

 higher beds, amongst which are seveal new species. The}' have been 

 omitted for the present, as being of the least importance, and because 

 they require additional study. 



In Mr. Lesquereux's report will be found an extremely interesting 

 account of the formation of fossil fuel, and the equivalency of the 

 various beds of coal throughout the field of our examination.- It re- 

 mains only necessary for me, on this occasion, to refer to each vein its 

 peculiar fossil shells, so far as they have been ascertained. 



It may be asked, how came marine shells to be imbedded in the 

 roof-shales, if the coal has been formed in fresh water ? They follow- 

 ed the influx of the sea after subsidence of the land, and are such as 

 usually live in shallow or brackish water, belonging to the phytiferous 

 (vegetable feeders,) and carniverous orders. The salt water gradually 

 killed out the coal flora — the last remains of which mixed with algse, 

 became entangled in the sediment of the ocean, and served to supply 

 bitumen, with which the dark shales that usually form the roof of the 

 coal are so frequently charged. 



Our observations go to show that wherever we found fossil remains 

 of the molusca abundant in the roof-shale, coal plants are rarely 

 found, whilst remains of marine plants are usually abundant. 



COAL NO. 1, B. 



This is the loAvest workable coal in the western basin, varying in 

 thickness from three to six feet, and characterized by a solitary molus- 

 ca* Lingula umbonatg, nob., plate X, fig. 4. It is opened and worked 

 by the Union Coal and Iron Company, one and a half miles below 

 Carrsville, in Livingston county, where it is an outlier, and the most 

 southern workable coal in the state. This vein has been opened and 

 worked by several companies along Tradewater river, in Crittenden 

 county-t It is most extensively worked on the property of Col. John 

 Bell, where it is from three and a half to six feet thick, and known as 

 the "Bell coal." Another opening was made into this vein on the' same 



•For the flora see Mr. Leo Lesquereux's report. 

 +See report of Dr. D. D. Owen, State Geologist. 



