MONTGOMERY COUNTY. 151 



There is certainly evidence that at some former period of time the 

 whole surface of the county was 50 to 75 feet higher than at present ; 

 that since the original drift deposition (it may have been just at the 

 close of the Drift period) large masses of these deposits were washed 

 off, leaving occasional mound like elevations, several of which may be 

 seen near Nokoinis, a few between the East and West forks, and the 

 hills between Hillsboro and Butler. 



Goal Measures. 



The upper Coal Measures appear in part in this county, and under- 

 lay all the superficial deposits, and include coal beds No. 11 and No. 13, 

 with a trace of No. 12, and embrace about 150 feet of rocks, reaching 

 from the base of No. 33 to No. 20 of upper Coal Measure section. 



Nos. 20 and 21.— In sec. 12, T. 10 N., E. 1 W., there crops out along 

 the creek 8 feet of sandy shale and blue limestone ; close by is an out- 

 crop of brown shaly soft limestone, containing Remipronites crassus 

 and Crinoid stems; a Mavhrocheilus and Spirifer cameratus were also 

 found. The exact thickness between 21 and 22 is uukuown ; the out- 

 crops are ten miles apart with no evidence of a continuous easterly 

 dip, but it is probable that 25 or even 50 feet may intervene. 



Boclcs on the Fast Fork of Shoal creek.— In sec. 24, T. 8 N., E. 3 W., 

 we have : 



Ft. 



1. Mostly dark lead-bine shales, upper part sandy "with brown nodules of iron stone, the lower 



two-thirds calcareous with many fossils, Productus Nebrascensis, Spirifer cameratus, Poterio- 

 crinus hemisphericux, Belleropkon inontfortianus, B. Carbonariu-?, Orthoceras cribrosum, Leda 

 belta-striata, a fossil near Soleniscus typicus, Bryozoa and a few branching corals 10 



2. Ash blue limestone, jointed and shelly on top ; contains Producing Prattcnianus, Chonetes, Avic- 



ulopecten, Pecten ? Aviculatus and Prod. Boonensis ? 



The last named limestone I regard as No. 22 of my upper Coal Meas- 

 ure section. North-east of Irving on East Fork, and down stream for 

 a mile, there are occasional outcrops of an ash blue hard shelly lime, 

 stone, abounding in a large variety of Productus Prattenianus; it also 

 contains P. costatus, P. punctatus, P. Nebrascensis, Spirifer cameratus 

 Avicidopecten carboniferus, Chonetes Yerneuiliana, Gh. Ftemingii, and a 

 branching coral. 



In sec 7, T. 8 N., E. 2 W., obtained the following section : 



Ft. 



1. Masses of tumbled limestone with ICcmipronitcs crassus, Productus Nebrascensis, Edmondia 



and Bryozoa ? 



2. Dove and brown clay shales 4 



3. Coal 1 



4. Greenish blue fireclay 2 



5. Olive shales changing to darker colored below, contains a few brown ironstone concretions, the 



middle part abounding in a large Pleurotomaria similar to one found by Mr Meek, at Rulo, in 

 Nebraska; the fossils are very fragile; a species of Machrucheilus is also found; thickness 

 exposed about 8 



