18 



ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 492 



Lesquereux, Leo, 1879-1884, Description of the coal flora of the Carbo- 

 niferous formation in Pennsylvania and throughout the United 

 States: Second Geological Survey of Pennsylvania, Report of 

 Progress P: Atlas, 87 pis., 1879; v. 1 and 2, p. 1-694, 1880; 

 v. 3, p. 695-977, pis. 88-111, 1884. 



Lindley, John, and William Hutton, 1831-33, Fossil flora of Great Britain 

 or figures and descriptions of the vegetable remains found in a 

 fossil state in this country. London: James Ridgway, v. 1, 

 223 p., 79 pis. 



Lindley, John, and William Hutton, 1833-35, Fossil flora of Great Britain 

 or figures and descriptions of the vegetable remains found in a 

 fossil state in this country. London: James Ridgway, v. 2, 

 208 + 28 p., 76 pis. 



Maxon, W. R. , 1912, The tree ferns of North America: Annual Report, 

 Smithsonian Institution, 1911, p. 463-491, 15 pis. 



Morgan, E. J., 1959, The morphology and anatomy of American species of 

 the genus Psaronius: Illinois Biological Monograph 27, 108 p., 

 82 figs. 



Noe, A. C, 1925, Pennsylvanian flora of northern Illinois: 

 State Geological Survey Bulletin 52, 113 p., 45 pis 



Illinois 



Stidd, B. N. , 1971, Morphology and anatomy of the frond of Psaronius: 

 Palaeontographica B, v. 134, p. 87-123, 10 figs., 3 tables, 

 16 pis. 



Weiss, Ernst, 1860, Ueber ein Megaphytum der Steinkohlen-Formation von 

 Saarbriicken: Zeitschrift der deutschen geologischen Gesell- 

 schaft, v. 12, p. 509-512. 



