DEVELOPMENT OF PALEOBOTANY IN THE ILLINOIS BASIN 73 



ROLFE, C. ¥., 1931, Investigations previous to the founding of the present State 

 Geological Survey: Illinois Geol. Survey Bull. 60, p. 23-28. 



ROTH, E. A., 1956, The anatomy and modes of preservation of genus Cardiocarpus (P,b) 



spina tus Graham: Kansas Univ. Sci. Bull., v. 37, pt. 1, p. 151-174-. 



ROTHWELL, G. W. , 1971, Additional observations on Conostoma anglo-germanicum and (P,b) 

 £. oblongum from the lower Pennsylvanian of North America: Palaeonto- 

 graphica, Abt. B, v. 131, p. I67-I78. 



ROTHWELL, G. W., and D. A. EGGERT, 1970, A Conostoma with a tentacular sarcotesta (P,b) 

 from the upper Pennsylvanian of Illinois: Bot. Gazette, v. 131, no. M-, 

 p. 359-366. 



SARTON, G., 19*1-2, Second preface to Volume XXXIV— Lesquereux (1806-89): Isis, v. 

 34, pt. 2, no. 94, p. 97-108. 



SAVAGE, T. E., 1914-, On the conditions under which the vegetable matter of the 



Illinois coal beds accumulated: Jour. Geology, v. 22, p. 75^-765; Illi- 

 nois Acad. Sci. Trans., v. 7, p. 100-110. 



SAVAGE, T. E., 1920, The Devonian formations of Illinois: Am. Jour. Sci., ser. k, 

 v. 49, p. I69-I82. 



SCHABILION, J. T., 1969, A study of the anatomy and taxonomy of the genus Spheno- (P,b) 

 phyllum : Univ. Kansas Ph.D. thesis, Lawrence, Kansas, 126 p. 



SCHLANKER, C. M. , and G. A. LEISMAN, 1969, The herbaceous Carboniferous lycopod (P,b,s) 

 Selaginella fraiponti comb, nov.: Bot. Gazette, v. 130, no. 1, p. 35-^1. 



SCHOOLCRAFT, H. R. , l822a, A memoir on the geological position of a fossil tree, 



discovered in the secondary rocks of the River Des Plaines: Read before 

 the American Geological Society. E. and E. Hosford, Albany, New York, 18 p. 



SCHOOLCRAFT, H. R., l822b, Remarkable fossil tree, found about fifty miles S.W. of 

 Lake Michigan, by his Excellency Gov. Lewis Cass and Mr. Henry R. School- 

 craft, in August, 1821, on the River Des Plaines, in the N.E. angle of 

 the State of Illinois: Am. Jour. Sci., ser. 2, v. H-, no. 2, art. 6, p. 

 285-291. 



SCHOOLCRAFT, H. R., 1825 , Travels in the central portions of the Mississippi Valley; 

 comprising observations on its mineral geography, internal resources, and 

 aboriginal population. Performed. . .in 1821: Collins and Hannay, New 

 York, 459 p. 



SCH0PF, J. M. , 1936a, The paleobotanical significance of plant structure in coal: (P,s) 

 Illinois Acad. Sci. Trans. (1935), v. 28, no. 2, p. 106-110. 



SCH0PF, J. M. , 1936b, Spores characteristic of Illinois Coal No. 6: Illinois Acad. (P,s) 

 Sci. Trans. (1935), v. 28, no. 2, p. 173-176. 



SCH0PF, J. M., 1937a, Preservation of plant material in coal balls from Nashville, (P,b) 

 Illinois: Illinois Acad. Sci. Trans. (1936), v. 29, no. 2, p. 159-160. 



SCH0PF, J. M. , 1937b, Two new lycopod seeds from the Illinois Pennsylvanian: Illi- (P,b,s) 

 nois Acad. Sci. Trans., v. 30, no. 2, p. 139-1^6; 1938, Illinois Geol. 

 Survey Circ. 28, 8 p. 



SCH0PF, J. M., 1938a, Coal balls as an index to the constitution of coal: Illinois (P,b) 

 Acad. Sci. Trans., v. 31, no. 2, p. I87-I89; 1939, Illinois Geol. Survey 

 Circ. 51, 3 p. 



SCH0PF, J. M., 1938b, A new cycadophyte and its relatives: Illinois Acad. Sci. (P,b) 

 Trans., v. 31, no. 2, p. 107-109; 1939, Illinois Geol. Survey Circ. 50, 

 3 P. 



SCH0PF, J. M., 1938c, A significant collection of American coal balls: Chronica (P,b) 

 Botanica, v. 4, nos. 4, 5, P» 38^-385. 



