PLATE 13 



All specimens photographed with transmitted light. Color of filter, when 

 used, indicated. 



Spencerisporites cf. S. radiatus (Ibrahim) n. comb p. 56 



Figure 



1. Spore with lips and contact areas split apart and partly folded. Total 

 diameter 375/*. Maceration 798 slide 13, lowest coal in diamond drill 

 core, Caseyville Group, Wabash County, Illinois. Green filter, same 

 scale as figures 2, 5a, (xlOO). 



2. Spore with torn bladder showing upper and lower bladder membranes. 

 Total diameter 365 /x. Maceration 798 slide 1RMK, lowest coal in dia- 

 mond drill core, Caseyville Group, Wabash County, Illinois. Green 

 filter, scale indicated below figure, (xlOO). 



3. Spore showing gouge-like appearance of radial striations and a narrow 

 marginal flange. Total diameter 385 /x. Maceration 798 slide 13, lowest 

 coal in diamond drill core, Caseyville Group, Wabash County, Illinois. 

 Green filter, same scale as figures 2, 5a, (xlOO). 



4. Spore showing high lips expressed as folds on upper surface of blad- 

 der. Total diameter 345 /x. Maceration 798 slide 13, lowest coal in 

 diamond drill core, Caseyville Group, Wabash County, Illinois. Green 

 filter, same scale as figures 2, 5a, (xlOO). 



5a. Spore with slightly wider marginal flange. Total diameter 314 p. 



Maceration 618 slide 3, Reynoldsburg Coal, Johnson County, Illinois. 



Scale indicated above figure, (xlOO). 

 5b. Same spore. Detail of spore body and radial striations. Green filter, 



same scale as figure 6, (x200). 



6. Detail of marginal flange. Maceration 618 slide 3, Reynoldsburg Coal, 

 Johnson County, Illinois. Scale indicated below figure, (X200). 



Spencerisporites cf. S. gracilis (Zerndt) n. comb p. 58 



7. Poorly preserved spore with wide marginal flange and reticulate- 

 appearing central area. Maximum dimension 443 /x. Maceration 519B 

 slide 3, DeKoven Coal, Williamson County, Illinois. Green filter, same 

 scale as figures 2, 5a, (xlOO). 



8. Small spore showing wide marginal flange and distinct reticulate- 

 appearing folds in central area. Total diameter 315/*. Maceration 879 

 slide 4, Harrisburg (No. 5) Coal, Edgar County, Illinois. Green filter, 

 same scale as figures 2, 5a, (xlOO). 



9. Spore with wide marginal flange which appears lobe-like in outline at 

 two of the corners. Total diameter 388 /x. Maceration 133, "Bogota" 

 Coal, Fayette County, Illinois. Green filter, same scale as figures 2, 

 5a, (xlOO). 



Calamospora cf. C. sinuosa (Potonie and Kremp) ex Horst p. 60 



10. Folded proximo-distal compression. Diameter 700 /x. Maceration 625A X 

 slide 10, Willis Coal, Gallatin County, Illinois. Scale indicated below 

 figure, (x75). 



Calamospora cf. C. laevigata (Ibrahim) Schopf, Wilson, and Bentall . . p. 60 



11. Oblique compression with relatively short suture and vaguely defined 

 contact areas. Diameter 314 fx. Maceration 600 slide 11, "LaSalle" Coal, 

 Bureau County, Illinois. Scale indicated below figure, (xl50). 



Calamospora sp p. 61 



12. Oblique compression of small spore with relatively thick coat. Thick- 

 ening of spore coat in contact area showing at upper margin. Diameter 

 185 fx. Maceration 600 slide 11, "LaSalle" Coal, Bureau County, Illinois. 

 Same scale as figure 11, (xl50). 



[128 



