52 Evolution and Distribution of Fishes 



If we compare this with the total production of oil 

 from the oil fields of Pennsylvania and New York up to 

 January, 1885, this amounted only to 26,000,000 barrels 

 of forty-two gallons, or one billion, ninety-two million gal- 

 lons in all. Sterry Hunt in calculating the oil contents of 

 the petroliferous dolomite of Chicago estimated "its petro- 

 leum content at one-tenth of one per cent, and the thick- 

 ness of the stratum at 500 feet, both of which figures are 

 probably within the limits." He accordingly estimated 

 "the petroleum contained in it to be more than 2,500,000 

 barrels to the square mile." Both of the above figures — 

 enormous though they may seem — fall far short of the 

 probable destruction of menhaden during any one year. 

 Now the total production of crude petroleum from all of 

 the oil fields of the world, up to 1914, was 5,593,262,936 

 barrels of 42 gallons, or a total of 234,917,043,312 gal- 

 lons (The American Petrol. Indust. (1916)258-59). If 

 we again accept it that 200 fishes are required to yield one 

 gallon of oil this would involve the sudden destruction of 

 only 47 trillions of fish, or the one twenty-thousandth part 

 of the number of menhaden estimated to be preyed on and 

 destroyed in a year. But, as will be frequently noted in 

 later pages, some of the fossil fishes that are surrounded by 

 zones of bituminous material in the different formations, 

 are only one-half to one-third the size of average men- 

 haden. On the other hand a considerable number of spec- 

 ies, notably those of the freshwater Pennsylvanian-New 

 York shales (pp- 134-35)? of the freshwater Solenhofen- 

 Bugey shales (p. 195), and of the marine Kansas-Texas 

 shales (p. 223-24) are equal to or larger than the menhaden. 

 So the above calculations can well stand as at least an ap- 

 proximately fair estimate of the average fish-yield. 



The world's production of petroleum, however, is at 

 present drawn from nearly every one of the geologic for- 

 mations, from the Silurian upward. Now in any one of 

 the many bituminous horizons listed, the wholesale destruc- 

 tion of fish-life must have been truly cataclysmic and wide- 

 spread. Furthermore, and contrary to past reasonings of 

 most geologists If we except those of Russell and one or two 

 others, the most celebrated fish-strata have their enclosed 



