GENUS RENISPORITES 



65 



mens extending completely around and 

 close to the suture. 



Spore coat. — Coat ranges from 2.5 to 10 ju, 

 in thickness, thickest around ends of su- 

 ture, golden yellow to yellowish brown by 

 transmitted light. 



Affinity. — Unknown. 



Discussion. — Spores of this genus are 

 much larger than most of those referred at 

 present to the genus Laevigatosporites 

 (Ibrahim) Schopf, Wilson, and Bentall. 

 Spores of Renisporites have a much thicker 

 spore coat and more clearly defined arcuate 

 ridges. The distinctive ornamentation, dis- 

 crete puncta completely traversing the coat 

 and groups of puncta, is unknown, at pres- 

 ent, on the spores of Laevigatosporites or 

 on any other plant spore. The puncta are 

 superficially similar to those found on the 

 unrelated disseminules of Tasmanites. 



The spores of Renisporites cannot be 

 considered, on the basis of present informa- 

 tion, as of medullosan affinity because of 

 their generally smaller size, lack of distal 

 grooves, straight rather than medially de- 

 flected suture, and punctate ornamentation. 

 In size they are comparable with, but 

 slightly larger than, the spores of the 

 medullosan Dolerotheca villosa Schopf 

 (1948), but do not possess the distal 

 grooves. Spores of Codonotheca do not pos- 

 sess distal grooves (Schopf, 1948), but do 

 have the typical deflection in the suture. 



Because of the size of these spores, one 

 would expect only a few to be found in the 

 minus 65-mesh residue upon which small 

 spore studies are based; unless very com- 

 mon, these spores would scarcely be notice- 

 able in the plus 65-mesh residue, especially 

 if the residues are examined dry. 



Renisporites is apparently represented 

 only in the Willis and Tarter Coals of Illi- 

 nois, but not in all samples of these two 

 coal beds that were examined. The correla- 

 tion of the two coals has been confirmed on 

 the basis of small spores (Kosanke, 1950). 



Renisporites confossus n. sp. 

 Plate 15, figures 4, 5; text figures 4, 5 



Description. — Spores monolete, large for 

 "small" spores, generally compressed par- 



LENGTH 



225/i 



LENGTH/BREADTH 



1.0 



1.2 



I. 3 



I. 4 



1.5 



Text fig. 4 (above). — Length-breadth measure- 

 ments, groups in 10^ intervals, from 59 spores of 

 Renisporites confossus. Lined area represents 

 holotype. 



Text fig. 5 (below). — Length-breadth proportions of 

 spores of Renisporites confossus, based on meas- 

 urements given in text figure 4. Lined area rep- 

 resents holotype. 



allel to the long axis, but rarely folded, 

 probably originally of a somewhat rotund 

 bean-shape. Length ranging from 126 to 



