20 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 480 



wrote concerning his acquaintance with Noe and the development of his doctoral 

 thesis: 



I became interested in paleobotany while employed as a preparator in the 

 Botany Department of the Field (Chicago) Museum of Natural History in the 

 late 1920s. Among other duties, I was assigned to work on the Carboniferous 

 Forest Diorama Restoration in the Geology Department, which work lasted for 

 several years. It was then that I became acquainted with Dr. Noe', as he was 

 consultant on this project. As a result, I became interested in fossil 

 plants, particularly from the geological aspect, and decided to do my grad- 

 uate work in this field under Dr. Noe". 



His thesis was an important work and involved the revision of Lesquereux's types 

 (Janssen, 1940a, b) . The Museum published Janssen's thesis as the first volume 

 in their new Scientific Series. 



Janssen applied quantitative techniques to the Mazon Creek flora (1945, 

 1946), as was later done with larger collections, such as the Carr and Daniels 

 collections at the University of Illinois, which were studied by Stewart (1950). 

 Janssen (1939) also prepared the first of the Illinois State Museum series in Pop- 

 ular Science, Leaves and Stems from Fossil Forests , which, according to Janssen, 

 ". . .was the outgrowth of a feeling by Dr. Noe and Director Deuel of the State 

 Museum that there was a need for such a book because there were no others of 

 this nature being published in the United States. I was not at any time on the per- 

 manent staff of the Illinois State Museum. " Janssen continued to write articles 

 for the interested public, including Fossil Forests of the Great Coal Age and The 

 Beginnings of Coal (Janssen, 1942, 1948). He retired as head of the Geology 

 Department, Marshall University, Huntington, West Virginia, in 1969. 



In the last 25 years Geological Surveys have made numerous contributions 

 on fertile specimens of the Mazon Creek flora (Schopf, 1948a; Kosanke, 1955; and 

 Pfefferkorn, Peppers, and Phillips, 1971). Additional studies have been made by 

 Delevoryas (1964a) and Taylor (1967a). From nodules found in the roof shale above 

 the Herrin Coal at the Carterville locality, Hibbert and Eggert (1965) described a 

 species of Paracalamostaohys . Visiting paleobotanists from Europe also have been 

 interested in the compression-impression plants (Chaloner, 1956, 1958; Bode, 1958, 

 1960; Lacey and Eggert, 1964). Read and Mamay (1964) included considerable in- 

 formation on Illinois compression floras in their discussion of the upper Paleozoic 

 floral zones and provinces of the United States, as did Darrah (1969) in his review 

 of upper Pennsylvanian floras. A brief stratigraphic comparison of Pennsylvanian 

 plants from Kansas with those from the Illinois Basin was made by Cridland, 

 Morris, and Baxter (1963). 



In connection with the Geological Society of America meeting in 1970, a 

 field trip was made into the northeastern Illinois area of the Colchester (No. 2) 

 Coal and the Francis Creek Shale. The field guidebook (Smith et al., 1970) pre- 

 pared for the trip contained several articles of interest to paleobotanists, partic- 

 ularly Depositional Environments in the Francis Creek Shale , by C. W. Shabica, 

 and A Comparison of the Floras of the Colchester (No. 2) Coal and Francis Creek 

 Shale, by Peppers and Pfefferkorn. The latter is the first integrated comparison 

 of floras from the coal and overlying shale of the Illinois Basin. It lists the taxa 

 present, gives percentages of taxonomic groups, and considers both spore succes- 

 sion in coals and the paleoecological aspects of compression floras. 



