GENUS LAEVIGATO-SPORITES 



27 



Reticulati-sporites muricatus sp. nov. 



Plate 4, figure 7 



Description. — Spores are radial, body is 

 essentially spherical, the outline is irregular- 

 ly crenulate due to the large muri. The 

 overall diameter measures 84 X 91.2 mi- 

 crons and the known size range is from 81.9 

 to 96.6 microns. The spore coat is reticulate 

 with large lacunae and thin but long muri. 

 The lacunae are up to 20 microns in width 

 and average 10 to 12 microns. The muri 

 are 8 to 10 microns high and about 2 mi- 

 crons wide. They are frequently folded 

 and twisted. The trilete mark, lips, and 

 commissure are present and distinct. The 

 rays of the holotype range in length from 

 23 to 31.5 microns. The spore coat ranges 

 from 2 to 4 microns in thickness exclusive 

 of the muri. 



Holotype. — Maceration 600 Slide 2, La- 

 Salle coal bed, Bureau County, Illinois. 



Discussion. — This species is distinctly an 

 upper McLeansboro form, usually fairly 

 abundant and easily recognized. As in R. 

 splendens sp. nov., the muri traverse the 

 trilete rays. 



Reticulati-sporites scrobiculatus sp. 

 nov. 



Plate 4, figure 6 



Description. — Spores are radial and es- 

 sentially spherical in outline. The holotype 

 measures 109 X HI microns, and the 

 known size diameter is from 102 to 116 mi- 

 crons. The spore coat has two types of 

 ornamentation : one, the reticulate type and 

 the other a very definite punctate condition 

 between the muri. The lacunae are very 

 large and regular and measure over 50 mi- 

 crons in width. The muri measure 4 to 5 

 microns in width and are about 3 microns 

 high. The trilete mark, lips, and commis- 

 sure are distinct. The rays of the holotype 

 range in length from 30 to 40 microns. The 

 spore coat exclusive of the muri measures 

 slightly more than 3 microns. 



Holotype. — Maceration 574 Slide 14, 

 Shoal Creek coal bed, Bond County, Illi- 

 nois. 



Discussion. — The punctate ornamenta- 



tion is so distinct that the reticulate con- 

 dition appears indistinct when compared 

 with other species of the genus. 



Reticulati-sporites splendens sp. nov. 



Plate 5, figure 4 



Description. — Spores are radial, and 

 spherical to subtriangular in outline with- 

 out folds. The holotype measures 58.27 X 

 56.7 microns, and the known size variation 

 is from 53 to 61 microns. The spore coat 

 is reticulate with widely spaced lacunae on 

 both proximal and distal surfaces. The 

 reticulate ridges (muri) may be as much as 

 2 microns wide and 6 microns high and the 

 lacunae may be as much as 12 microns in 

 length. The tetrasporic mark is distinct 

 as are the lips and commissure. The rays 

 vary in length from 14 to more than 20 

 microns in length. The apex of the rays 

 is frequently difficult to see due to the 

 reticulate ridges which apparently traverse 

 the rays. The spore coat is more than 2 

 microns thick and when joined by a ridge 

 (muri) it is as much as 8 microns thick. 



Holotype.— Maceration 587 Slide 18, 

 Battery Rock Coal bed, Hardin County, 

 Illinois. This species is known to occur 

 in the Wayside and "Sub-Babylon" coal 

 beds through the Tarter and Willis coal 

 beds of lower Tradewater age. 



Discussion. — R. splendens proves that 

 the reticulate ridges (muri) are formed 

 after the second division of the spore 

 mother cell, because the ridges traverse the 

 trilete rays. 



GENUS Laevigato-sporites (Ibrahim, 

 1933) emend., S. W. and B., 1944 



Plate 5, figures 3, 6-11 ; Plate 16, figures 2, 6 



Spores of the genus Laevigato-sporites 

 are known to occur in Illinois in coal beds 

 ranging from the Caseyville group through- 

 out the entire Pennsylvanian. The genus 

 is also known to occur in almost every coal 

 of Pennsylvanian age that has been studied 

 in the United States and Europe. Further- 

 more, Berry (1937) reports its presence in 

 the Permian of Ohio, and Wilson and 

 Webster (1946) report that similar forms 



