168 Trans. Acad. Sci. of St. Louis 
Pentremites pyriformis Troost. 
1835, Transactions, Aprechace Geological Society, vol. 1, pt. 
2, p. 228, pl. 10, fig. 
Sub-Carb.; near sce: Tennessee; Mount Sano, Alabama; 
Kentucky. 
Pentremites pyriformis Say, Owen. 
1842, American Journal of Science, vol. 43, p. 20, fig. 3. 
Pentremites pyriformis Say, CHristy. 
1848, Christy’s Letters on Geology, pl. 4, fig. 6. 
Carboniferous limestone; Huntsville, Alabama. 
Pentremites pyriformis Say, Troost. 
1850, Proceedings, American Association for the Advancement 
of Science, vol. 1849 (1850), p. 60. 
Pentremites pyriformis Say, Hatt. . 
1858, Report on the Geological Survey of Iowa, vol. 1, pt. 2, 
p. 693, pl. 25, fig. 16. 
Kaskaskia limestone; Chester, Illinois; Huntsville, Alabama. 
Pentremites pyriformis Say, BrLLincs. 
1859, Geological Survey of Canada, Decade 4, p. 20, figs. 5 and 7. 
Pentremites pyriformis Say, SHUMARD. 
865, Transactions, St. Louis Academy of Science, vol. 2, No. 2, 
p- 385 
Pentremites pyriformis Say, SAFFORD. 
1869, Geology of Tennessee, p. 359, text fig. 1. 
Chester group; Cowan and other localities, Tennessee. 
Pentremites pyriformis Say, BILLINGs. 
1870, American Journal of Science, vol. 50, p. 228. 
Pentremites pyriformis Say, WACHSMUTH and SPRINGER. 
1879, Aaoecsscr Academy of Natural Sciences, Philadelphia, pl. 
17, fig. 
Pentremites pyriformis Say, WHITE. 
1881, Second Annual Report, Department of Statistics and Ge- 
ology of Indiana, p. 511, pl. 7, fig. 9. 
Chester group; Down Hill, Crawford County, Indiana. 
Pentremites pyriformis Say, KEYEs. 
1894, Missouri Geological Survey Paleontology, vol. 4, pp. 135- 
136 (no figs.) 
Kaskaskia Eoce St. Marys, Missouri. 
