THEIR USE IN CORRELATION 121 



PLATE 14 



Fig. 1. — Wilsonia vesicatus sp. nov. genotype, maceration 600 Slide 2, LaSalle coal bed, 

 Bureau County, Illinois, overall dimensions are 79.8 X 75.6 microns. 



Fig. 2. — Reconstruction of a transverse proximal view of the genotype W '. vesicatus. 



Fig. 3. — Diagrammatic cross-section of fig. 2 illustrating the bladder which overlaps the 

 circular body. 



Fig. 4. — W. delicata sp. nov. holotype, maceration 540-C Slide 8, No. 6 coal bed, Fulton County, 

 Illinois, overall dimensions are 92.4 X 86.1 microns. 



Figs. 5-6. — Thin section of cannel coal from Witham (1833, PI. 11, figs. 4 and 5) believed to be 

 the first thin sections of coal ever made. Fig. 5 is a transverse section and fig. 6 a 

 cross-section illustrating megaspores and possibly small spores. 100X. 



