GENUS TRILETES 



31 



(maceration 938B) , and Wiley (macera- 

 tion 525A) Coals. In the Tradewater 

 Group as a whole, spores of this species 

 seem to be most abundant in a few sam- 

 ples of the Tarter (maceration 914) , Rock 

 Island (No. 1) (maceration 929) and 

 Murphysboro (?) (macerations 628A-B) 

 Coals. 



In the Carbondale Group the spores are 

 abundant in one sample of the Colchester 

 (No. 2) Coal (maceration 826) and pres- 

 ent in another (maceration 603B) . They 

 are rare in the Indiana Coal IV (macera- 

 tion 881) and Springfield (No. 5) Coal 

 (maceration 630) , but more common in 

 another sample of the Harrisburg (No. 5) 

 Coal (maceration 583) . 



In the McLeansboro Group the spores 

 are rare in Friendsville Coal (maceration 

 490D) , present in the "Merom" (macera- 

 tion 146) and "Woodbury" (maceration 

 703) Coals, and common in the "LaSalle" 

 Coal (maceration 600) . Some large spores 

 with bulbose "ears," occurring in the 

 McLeansboro Group, may be referable to 

 Triletes auritus var. grandis Zerndt. 



Triletes augustae (Loose) Schopf, 

 Wilson, and Bentall, 1944 

 (sensu Potonie and Kremp) 



Plate 7, figures 12, 13 



1934 Zonales-sporites augustae Loose, p. 150; pi. 



7, fig. 32. 

 1944 Triletes augustae (Loose) Schopf, Wilson, 



and Bentall, p. 20. 



Discussion. — These spores range, accord- 

 ing to Potonie and Kremp (1956), from 

 900 to 1100 fi in diameter. Their equatorial 

 outline is strongly rounded deltoid. The 

 projecting, strongly developed trilete rays 

 are ridge-like and give the spores a charac- 

 teristic outline. Potonie and Kremp note 

 that the coat may be densely covered with 

 small depressions. The species is reported 

 from the Upper Westphalian B-C of the 

 Ruhr Basin. 



These spores are here distinguished from 

 those of Triletes auritus (which in Dijk- 

 stra's interpretation includes T. augustae) 

 because there is no evidence that spores of 

 both types may be borne in the same cone. 



The spores possess thick straight ridges 

 from apex to spore margin, not thin and 

 abruptly rising at the proximal pole as are 

 those of Triletes auritus. The "ears" are 

 the pointed radial extremities and are not 

 bulbose. Small depressions in the coat, es- 

 pecially noticeable on the proximal sur- 

 face, may be present. Two extremes of ray 

 development are illustrated on plate 7. On 

 one very small specimen the rays are low 

 (pi. 7, fig. 13) ; on a larger specimen the 

 bases of the rays are thick but the lips ap- 

 pear high and fluted. Most specimens are 

 similar to those illustrated by Potonie and 

 Kremp (1955, pi. 6, figs. 44-47), for this 

 species. The maximum size range noted is 

 from 855 to 1250 p. The spores may be 

 brown to black by reflected light. 



Occurrence. — In the Tradewater Group 

 these spores are present in the Babylon 

 Coal (macerations 588, 145B) ; abundant 

 in the Pope Creek Coal (maceration 602) ; 

 rare to common in the Rock Island (No. 1) 

 Coal (macerations 626, 589, 627) and 

 Murphysboro (maceration 549) Coal; com- 

 mon to abundant in the New Burnside 

 Coal (macerations 938B-C) ; rare in the 

 DeKoven (?) Coal (maceration 62 ID) . In 

 the Carbondale Group these spores are 

 common in the Colchester (No. 2) Coal 

 (maceration 580) , Summum (No. 4) Coal 

 (maceration 463) , and Harrisburg (No. 5) 

 Coal (maceration 583) . They are rare in 

 the "LaSalle" Coal (maceration 600) of 

 the McLeansboro Group. 



Triletes appendiculatus 

 Maslankiewiczowa, 1932 



J 932 Triletes appendiculatus Maslankiewk/oua, 



p. 163, fig. 39. 

 1946 Triletes appendiculatus Maslankiewiczowa, 



in Dijkstra, p. 34; pi. 16, figs. 176, 177. 



Triletes appendicular s ? 

 Plate 7, figure 14 



Discussion. — The spores of Triletes ap- 

 pendiculatus, according to Potonie and 

 Kremp (1956), are about 800 to 900 ^ in 

 diameter. The auriculate projections or 

 "ears" are longer than one-half the radius 

 of the spore body and their basal width is 

 more or less equal to the equatorial dis- 



