132 GEOLOGY OF ILLINOIS. 



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Ko* 44* (Sandy limestone and sandstone, fossils 4$ 



No. 45. Sandy shale , 30 



No. 46. Sandstone, fossils 8 



No. 47. Gray shale and sandstone 3D 



No' 49' \ Shoal creek limestone 4 



No! 50' 1 



No. 51. >Clay and bituminous shale lGi 



Ko. 52.) 



No. 53. Coal. No. 9 10 



No. 54. Fireclay .' 2 



No. 55. Sandy shale 4 



The rocks occupying the highest geological position are those seen on 

 Dry Fork and Lake Fork. On a branch of Lake Fork, near McCrack- 

 en's, I observed the following beds : 



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No. 26. Brown and drab clay shales 8 



No. 27. Black shaly limestone, with Bryozoa, 10 



No. 28. Coal, No. 12 .' 3 



No. 29. Clay shales, the lower part a nodular limestone bed 7 



On the head of Dry Fork the same beds occur, thus : 



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1. Limestone, with fossils, Hemipronites crassus, Athyris svbtilita. and Synocladia biscrialis - 



2. Shales, with brown iron stone nodules 5 



3. Shale -. 8 



4. Limestone, No. 31 - 10 



Part of the same section, one mile down stream, ^appears as follows : 



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1. Dark coarse shaly limestone, abounding in Polypcra, Synocladia biserialis, contains also 



Productus Xebrascensis, Aviculopectcn and Spiriferina KentuckensU 4 



2. Drab clay shale 8 



3. Buff limestone, referred to No. 31, with many remains of Crinoids, contains also Productus 



longispinus 5 



On Lake Fork, near McCracken's coal bank, limestone ("No. 31) is 

 thirteen feet thick and has many minute particles of calcareous spar 

 disseminated ; the bottom bed of one foot consists of dark ash-colored 

 limestone ; beneath this is four feet of bitumiuous and blue shale resting 

 on seventeen inches of coal. This coal I have marked as No. 11, count- 

 ing upward, and its place in the section is No. 33. 



From this downward, according to the record of the Litchfield boring, 

 there is thirty-nine feet vertical thickness to the next rocks comiug 

 under my observation. In a descending series we next observe on the 

 tributaries of Dry Fork, in sec. 19, T. 6 K, B, ± W.: 



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No. 34. Clay sha'e 12 



No. 34$. Rough calcareo-ferruginous bed, with Bellerophon carbonarius, Pleurotomaria sphte- 



rulata, and ALacrocheilus '. 3 



No. 35. Lead-blue calcareous shale 8 



No. 35$. Bituminous shale 8 



No. 36. Lead-blue calcareous slra T e, fossiliferous : it is sometimes a limestone, contains Pro- 

 ductus longispinus, Chonetes variolata? Ch. Yerneuilianus and Lophophyllum prolife- 



rum 2 



No. 37. Bituminous coal 7 



No. 36. Dark olire fire-clay 4 



No. 39. Green sandy shales, containing rough brown nodules -\ 3 



