PLATE 6 



All specimens photographed with reflected light, unless otherwise indicated. 

 Color of filter, when used, also indicated. 



Triletes indianensis Chaloner p. 26 



Figure 



1. Inner surface of one of three segments of apical prominence. Lip at 

 apex up to 226 /j, in height. Maceration 943 slide 12, coal in the Bethel 

 (Mooretown) Formation, Hardin County, Kentucky. Transmitted light. 

 Red filter, same scale as figure 3, (xl50). 



2. Proximo-distal compression showing pyramidal apical prominence. 

 Diameter 1195^. Maceration 943 slide 1, coal in the Bethel (Moore- 

 town) Formation, Hardin County, Kentucky. Same scale as figure 4, 

 (X30). 



3. Maximum development of spines observed. Spines up to 20 fx in length. 

 Maceration 943 slide 14, coal in the Bethel (Mooretown) Formation, 

 Hardin County, Kentucky. Transmitted light, red filter, scale indi- 

 cated below figure, (xl50). 



Triletes echinoides Chaloner p. 47 



4. Fragment of spore coat showing detail of spines. Length of straight 

 spine 1595 /x. Maceration 888 slide 3, carbonaceous layer near base (?) 

 of Glen Dean Formation, Wise County, Virginia. Transmitted light, 

 scale indicated below figure, (x30). 



5a. Lateral compression of a poorly preserved example. Spines present 

 on contact areas, but longer and more closely spaced on distal sur- 

 face. Total length including ornamentation 3560 /*. Maceration 888 

 slide 1, carbonaceous layer near base (?) of Glen Dean Formation, Wise 

 County, Virginia. Scale indicated below figure, (xl5). 



5b. Same spore. View of other side showing height of lips and contact 

 area spines. Same scale as figure 5a, (xl5). 



Triletes cf. T. eregliensis Dijkstra p. 48 



6. Two spores still in tetrad association along one contact face. Equa- 

 torial dimension, measured below arcuate ridge, of larger spore 1130 y.. 

 Maceration 604A slide 6, Tarter Coal, Fulton County, Illinois. Same 

 scale as figure 8, (x20). 



Triletes glabratus Zerndt (sensu Dijkstra) p. 28 



7. Immature spore with subtriangular outline. Diameter 665 /x. Macera- 

 tion 463 slide 2, Suraraum (No. 4) Coal, Jersey County, Illinois. Same 

 scale as figure 4, (x30). 



8. Mature spore. Suture open. Diameter 2100 /x. Maceration 583 slide 1, 

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

 below figure, (x20). 



9. Large specimen with slightly parted low lips. Diameter 2200 /x. Macera- 

 tion 878 slide 1, Grape Greek (No. 6) Coal, Edgar County, Illinois. 

 Same scale as figure 8, (x20). 



10. Proximo-distal compression. Suture open. Diameter 2345 fx. Spore coat 

 26-31 ix in thickness. Maceration 600 slide 4, "LaSalle" Coal, Bureau 

 County, Illinois. Transmitted light. Red filter, same scale as figure 8, 

 (X20). 



[115 



