PENNSYLVANIAN SPORES OF ILLINOIS 



AND 



THEIR USE IN CORRELATION 



BY 



R. M. KOSANKE 



INTRODUCTION 



The term spore may be defined in a 

 broad sense as a reproductive organ 

 or body formed by plants, and in the animal 

 kingdom by members of the Class Sporozoa 

 of the Phylum Protozoa. The spores iso- 

 lated from Illinois coal beds are all de- 

 rived with a few possible exceptions from 

 vascular plants. 1 All vascular plants pro- 

 duce spores or spore equivalents of which 

 there are several types : homosporous spores, 

 which are essentially the same size ; male 

 microspores and female megaspores of 

 heterosporous plants; and male spores 

 (microspores, prepollen, or pollen), and 

 female gametophytes of primitive seed 

 plants. 



All vascular plants produce either homo- 

 sporous spores or male microspores, or in 

 more highly developed vascular plants, their 

 equivalents. Megaspores are not produced 

 by all vascular plants. For this reason, and 

 because there are many more male spores 

 produced than megaspores, the homosporous 

 spores, microspores, and prepollen (small 

 spores) have been selected for the investi- 

 gation of their possible use in the correlation 

 of Illinois coal beds. 



The correlation of Illinois Pennsylvanian 

 strata is a complex problem, as is attested 

 by the numerous publications on the subject 

 from the time of Worthen and his asso- 

 ciates. Correlations using biological evi- 

 dence have been of considerable value. The 

 work of Dunbar and Henbest on the Fusuli- 

 nidae, Schopf's megaspore publications, and 

 Cooper's ostracod studies are examples. 

 However, there still exist numerous per- 

 plexing coal correlation problems, and 

 proved key beds are needed. 



Plants with definite conductive elements which are 

 above the mosses and liverworts in the phylogenetic sequence. 



There are more than 50 named coal beds 

 in Illinois, and in addition there are a 

 number of unnamed thin coal beds. The 

 spore content of many of these coal beds has 

 been extensively examined ; other beds still 

 need to be studied over a wider lateral 

 distribution. 



OBJECTIVES 



The main objectives of this investigation 

 were to determine the feasibility of corre- 

 lating Illinois coal beds by means of plant 

 spores, and to provide a paleobotanical basis 

 for correlating as many of the coal beds as 

 possible. In order to accomplish these 

 objectives, it was first necessary to prepare 

 and study the small spores from numerous 

 coal beds, to identify old and describe new 

 genera and species, and to determine the 

 vertical and lateral distribution of each 

 species. 



Variation in the abundance of genera and 

 species (both lateral and vertical), were 

 also studied, as well as their zonation within 

 portions of coal beds. 



HISTORY OF SPORE STUDIES 



The history of spore studies, given by 

 various authors, is very complete. The 

 following paragraphs give the more im- 

 portant contributions. 



The presence of fossil plant spores was, 

 in all probability, first observed by Mr. 

 Henry Witham (1833, p. 50, PI. 11, figs. 4 

 and 5). He emp^yed William Nichol's 

 method of thin sectioning to some cannel 

 coal from Lancashire and noted " . . . . de- 

 cided traces of organization." Witham 

 stated that he was inclined to believe that 

 these traces of organization might possibly 

 be the remains of a monocotyledonous plant 



[7 



