170 
Kirtley F. Mather 
1860. Productus asperus. McChesney, Desc. New Pal. Foss., p. 34. 
Coal Measures: LaSalle and Springfield, Illinois. 
1861. Productus Rogersi. Newberry, Ives’s Colo. Expl. Exped., p. 121. 
Coal Measures: Pecos Village and Kansas. 
1865. Productus asper. McChesney, 111. New Spec. Foss., pi. 1, figs. 7a-b. 
1866. Strophalosia herrescens. Geinitz, Carb. und Dyas in Nebr., p. 49. 
Bellevue, Plattsmouth, Nebraska City, and Bennett’s Mill, Ne- 
braska. 
1868. Productus nehrascensis. McChesney, Trans. Chicago Acad. Sci., 
vol. 1, p. 24, pi. 1, figs. 7a, b. 
Coal Measures: LaSalle and Springfield, Illinois. 
1872. Productus Nehrascensis. Meek, U. S. Geol. Surv. Nebr., p. 165, pi. 
2, fig. 2; pi. 4, fig. 6; pi. 5, figs, lla-c. 
Upper Coal Measures: Nebraska City, Wyoming, Bennett’s Mill, 
Rock Bluff, Plattsmouth, Bellevue, and Omaha, Nebraska. 
Coal Measures: Illinois; Missouri; Iowa; Kansas; New Mexico. 
1873. Productus Nehrascensis. Meek and Worthen, Geol. Surv. 111., vol. 
5, p. 569, pi. 25, fig. 8. 
Coal Measures: Sangamon and LaSalle Counties, Illinois. 
1876. Productus Nehrascensis. White, Powell’s Rep. Geol. Uinta Mts., 
p. 90. 
Lower Aubrey group: Confluence of Grand and Green Rivers. 
1877. Productus Nehrascensis. White, U. S. Geog. Surv. west of 100th 
Merid., vol. 4, p. 116, pi. 8, figs. 3a-d. 
Carboniferous: Camp Apache and Carrizo Creek, Maricopa 
County, Arizona; Rubyville, Schell Creek range, and top of Grass 
Mountain, Ely Range, Nevada; Meadow Creek, south of Fillmore, 
Utah. 
1883. Productus asperus. Hall, Rep. N. Y. State Geol., for 1882, pi. (19) 
50, figs. 5-7. 
Coal Measures: LaSalle, Illinois. 
1884. Productus Nehrascensis. White, 13th Rep. Geol. Surv. Ind., p. 122, 
pi. 24, figs. 7-9. 
Coal Measures: Fountain, Vermilion, Parke, and Vigo Counties, 
Indiana. 
1886. Productus Nehrascensis ?. Heilprin, 2nd Geol. Surv. Penn., Ann. 
Rep. for 1885, p. 453, fig. 4c; p. 440, figs. 4-4b. 
Mill Creek limestone. Upper Coal Measures: Wilkesbarre, Penn- 
sylvania. 
1886. Productus Nehrascensis ?. Heilprin, Proc. and Coll. Wyo. Hist, and 
Geol. Soc., vol. 2, pt. 2, p. 268, figs. 4, 4b. 
Mill Creek limestone. Upper Coal Measures: Wilkesbarre, Penn- 
sylvania. 
1887. Productus Nehrascensis. Herrick, Bull. Sci. Lab. Den. Univ., vol. 
2, p. 49, pi. 2, fig. 30. 
Coal Measures: Flint Ridge, Ohio. 
