66 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 480 



KRICK, H. V., 1932, Structure of seedlike fructifications found in coal balls from (P,b) 

 Harrisburg, Illinois: Bot. Gazette, v. 93, no. 2, p. 151-172. 



LACEY, W. S., and D. A. EGGERT, 1964- , A flora from the Chester Series (upper Mis- (M,c) 

 sissippian) of southern Illinois: Am. Jour. Botany, v. 51, no. 9, P« 

 976-985. 



LANGFORD, GEORGE, 1958, The Wilmington coal flora from a Pennsylvanian deposit in (P,c) 

 Will County, Illinois [2nd ed. ]: Esconi Assoc, Downers Grove, Illinois, 

 360 p. 



LANGFORD, GEORGE, I963, The Wilmington coal fauna and additions to the Wilmington (P,c) 

 coal flora from a Pennsylvanian deposit in Will County, Illinois: Esconi 

 Assoc, Downers Grove, Illinois, 280 p. 



LEE, H. W. , 1964, A modified method of coal maceration and a simple technique for 

 slide preparation: Micropaleontology, v. 10, no. 4-, p. 4-86-4-90. 



LEIGHTON, M. M. , 1931, The State Geological Survey during the period 1923-1930: 

 Illinois Geol. Survey Bull. 60, p. 4-5-61. 



LEISMAN, G. A., 1961, Further observations on the structure of Selaginellites eras- (P,b,s) 

 sicinctus : Am. Jour. Botany, v. 4-8, no. 3, p. 224-229. 



LEISMAN, G. A., 1962a, A Spencerites sporangium and associated spores from Kansas: 

 Micropaleontology, v. 8, no. 3, p. 396-4-02. 



LEISMAN, G. A., 1962b, Spencerites moorei comb. nov. from southeastern Kansas: (P,b,s) 

 Am. Midland Naturalist, v. 68, no. 2, p. 34-7-356. 



LEISMAN, G. A., 1964-a, Mesidiophyton paulus gen. et sp. nov., a new herbaceous (P,b) 



sphenophyll: Palaeontographica, Abt. B, v. 114-, nos. 4-6, p. 135-1^6. 



LEISMAN, G. A., 1964-b, Physostoma c ale ara turn sp. nov., a tentacled seed from the (P,b) 

 middle Pennsylvanian of Kansas: Am. Jour. Botany, v. 51, no. 10, p. 

 IO69-IO75. 



LEISMAN, G. A., 1968, A century of progress in paleobotany in Kansas: Kansas Acad. 

 Sci. Trans., v. 71, p. 301-308. 



LEISMAN, G. A., 1970, A petrified Sporangiostrobus and its spores from the middle 

 Pennsylvanian of Kansas; Palaeontographica, Abt. B, v. 129, p. 166-177. 



LEISMAN, G. A., and J. L. BUCHER, 1971, Variability in Calamocarpon ins ignis from (P,b) 

 the American Carboniferous: Jour. Paleontology, v. 4-5, p. 4-94-501. 



LEISMAN, G. A., and CHARLES GRAVES, 1964-, The structure of the fossil sphenopsid (P,b,s) 

 cone, Peltastrobus reedae : Am. Midland Naturalist, v. 72, no. 2, p. 

 4-26-437. 



LEISMAN, G. A., and J. S. PETERS, I97O, A new pteridosperm male fructification from (P,b,s) 

 the middle Pennsylvanian of Illinois: Am. Jour. Botany, v. 57, no. 7, 

 p. 867-873. 



LEISMAN, G. A., and JE0RG ROTH, 1963, A reconsideration of Stephanospermum : Bot. (P,b) 

 Gazette, v. 124-, p. 231-240. 



LEISMAN, G. A., and P. A. SPOHN, 1962, The structure of a Lepidocarpon strobilus 



from southeastern Kansas: Palaeontographica, Abt. B, v. Ill, p. 113-125. 



LEISMAN, G. A., and B. M. STIDD, I967, Further occurrences of Spencerites from the (P,b,s) 

 middle Pennsylvanian of Kansas and Illinois: Am. Jour. Botany, v. 54-, 

 no. 3, p. 316-323. 



LENZ, L. W., 1942, Contributions to our knowledge of American Carboniferous floras. (P,b) 

 3. Stipitopteris : Missouri Bot. Gardens Annals, v. 29, no. 2, p. 59-64. 



LESQUEREUX, LEO, 1858, On the order in the coal measures of Kentucky and Illinois (P,c) 

 and their relations to those of the Appalachian coal-field: Am. Jour. Sci., 

 arts. ser. 2, v. 26, no. 76, p. 110-112. 



