PLATE 7 



All specimens photographed with reflected light. 



Triletes mamillarius Bartlett (sensu Dijkstra) p. 28 



Figure 



1. Immature spore with subtriangular outline. Diameter 820 p. Macera- 

 tion 625 A 2 slide 1, Willis Coal, Gallatin County, Illinois. Same scale 

 as figure 15a, (x20). 



2. Slightly larger spore with more rounded outline. Maceration 625A X 

 slide 2, Willis Coal, Gallatin County, Illinois. Same scale as figure 

 15a, (X20). 



3. Still larger example with open trilete suture. Maceration 625A a slide 2, 

 Willis Coal, Gallatin County, Illinois. Same scale as figure 15a, (x20). 



4. One of largest examples. Maceration 625Aj slide 2, Willis Coal, Galla- 

 tin County, Illinois. Same scale as figure 15a, (x20). 



5. Largest dry specimen observed in Willis Coal. Diameter 1540^. Mac- 

 eration 625B slide 4, Willis Coal, Gallatin County, Illinois. Same scale 

 as figure 15a, (x20). 



6a. Characteristic example showing small contact area spines and well de- 

 veloped distal spines. Suture open. Maceration 795 slide 1, coal in 

 Caseyville Group, Wabash County, Illinois. Same scale as figure 15a, 

 (x20). 



6b. Same spore. Distal view. Same scale as figure 15a, (x20). 



Triletes auritus Zerndt (sensu Potonie and Kremp) p. 30 



7-9. Proximo-distal compressions illustrating the range in size and "ear" 

 configuration of spores of the species from one coal. Total diameter 

 of spores 855//,, 955//,, and 1205^, respectively. Maceration 733c slide 

 1, Battery Rock Coal, Crittenden County, Kentucky. Same scale as 

 figure 16, (x25). 



10. Proximo-distal compression. Maximum dimension 830 /x. Maceration 

 914 slide 1, Tarter Coal, Mercer County, Illinois. Same scale as figure 

 16, (x25). 



11. Lateral compression showing highly developed "ears" and slight apical 

 prominence. Maximum dimension 1110/*. Maceration 604A slide 2, 

 Tarter Coal, Fulton County, Illinois. Same scale as figure 16, (x25). 



Triletes augustae (Loose) Schopf, Wilson, and Bentall (sensu Potonie and Kremp p. 31 



12. Proximo-distally compressed spore with the highest lips observed for 

 spores of this species. Maximum dimension 1095 /t. Maceration 588 

 slide 2, Babylon Coal, Fulton County, Illinois. Same scale as figure 

 16, (x25). 



13. Small example with low, straight rays. Diameter 925 /*. Maceration 602 

 slide 5, Pope Creek Coal. Fulton County, Illinois. Same scale as figure 

 16, (x25). 



Triletes appendiculatus ? Maslankiewiczowa p. 31 



14. Spore with one "ear" and portion of one interradial area broken away. 

 Width of largest ear 410 /*. Maximum dimension 1120/x. Maceration 

 950A slide 1, coal in Tradewater Group, Grundy County, Illinois. Same 

 scale as figure 16, (x25). 



Triletes (Auriculati) spp p. 32 



15a. Spore with low ridge-like lips. Total diameter 1900 /t. Maceration 583 

 slide 1, Harrisburg (No. 5) Coal, Wabash County, Illinois. Scale indi- 

 cated below figure, (x20). 

 15b. Same spore. Distal view. Same scale as figure 15a, (x20). 



16. Lateral compression with slightly undulatory arcuate ridges and pitted 

 contact areas. Maximum dimension 1795 /*. Maceration 583 slide 1, 

 Harrisburg (No. 5) Coal, Wabash County, Illinois. Scale indicated 

 below figure, (x25). 



17. Proximo-distal compression. Diameter 1130 /i. Maceration 703 slide 1, 

 "Woodbury" Coal, Cumberland County, Illinois. Same scale as figure 

 16, (X25). 



18. Spore with undulatory arcuate ridges, pitted contact areas, and straight 

 rays. Diameter 1300 /*. Maceration 811 slide 1, "Divide" Coal, Jeffer- 

 son County, Illinois. Same scale as figure 16, (x25). 



[116] 



