SPORE DISTRIBUTION — CARBONDALE 



89 



T. rugosus, but no spores of Spencerispo- 

 rites cf. 5. gracilis, which are fairly common 

 in the DeKoven Coal. 



A pre-No. 2 coal (maceration 62 ID) , 

 penetrated by a rotary drill in Edwards 

 County, has a large spore assemblage much 

 more similar to that of maceration 936 

 than to that of the DeKoven Coal. This 

 coal does not contain any zonate spores, but 

 contains the others listed for the unnamed 

 coal (maceration 936) 9 feet above the De- 

 Koven Coal. In addition a few spores of 

 Trilctes mamillarius, Cystosporites gigan- 

 teus, and possibly one of T. augustae are 

 present. 



Miscellaneous Coals 



Two of the lower coals from the Illinois 

 Clay Products pit near Goose Lake, Grundy 

 County, were examined. The Colchester 

 (No. 2) Coal mined in this area lies above 

 these coals outside the vicinity of the pit. 



The lower of the two coals may be as 

 much as 6y 4 inches thick and is persistent 

 but somewhat irregular in thickness, thin- 

 ning to 1 1/9 inches within the area of the 

 pit (Doehler, 1957) . The following genera 

 and species were identified from this coal 

 at its maximum thickness (maceration 

 950A-B) : 



Monoletes ( A » p ) 



Triletcs superbus (P»P) 



Cystosporites varius ( -, R) 



T. mamillarius ( -, R) 



T. appendiculatus ? ( -, R) 



T. ramosus ( -, R) 



The other sample (maceration 949) of this 

 coal contains only one spore of Spenceri- 

 sporites, unidentifiable as to species. Tri- 

 letcs appendiculatus? is known from only 

 one other sample, the Tarter Coal (macera- 

 tion 604A) . T. superbus is known from the 

 "Sub-Babylon" (maceration 144) , Willis 

 (maceration 625A) , and Rock Island (No. 

 1) (maceration 929) Coals. 



The upper of the two coals, about 3i/2 

 inches thick, is not persistent. Maceration 

 951 contained only abundant spores of 

 Monoletes. 



Summary 



The lower coals of the Tradewater 

 Group, especially the Tarter and Willis 

 Coals, are characterized by a wide variety 



of megaspores and a maximum develop- 

 ment of some of the zonate spores, such as 

 those of Triletcs brasserti. In addition 

 Renisporites and Punctatisporites cf. P. 

 obesus seem to be restricted to these coals. 

 With the exception of one sample of the 

 Tarter Coal (maceration 914) , the coals 

 of the Tradewater Group lack spinose 

 lageniculate spores that are so common in 

 the coals of the Caseyville Group. How- 

 ever, the smooth, lageniculate megaspores 

 are prominent in the Rock Island (No. 1) , 

 Murphysboro, and younger coals of the 

 Tradewater Group. Parasporites and Spen- 

 cerisporites cf. S. gracilis, although never 

 abundantly represented, are conspicuous in 

 several of the upper coal beds of the Trade- 

 water Group. Triletes glabratus, repre- 

 sented in the "Makanda" Coals of the 

 Caseyville Group and generally conspicu- 

 ous in the coals of the Carbondale Group, 

 has not been recognized in Tradewater 

 Coals. 



CARBONDALE GROUP 



The Carbondale Group, next higher 

 stratigraphic division of the Pennsylvanian 

 in Illinois, extends from the base of the 

 Palzo Sandstone in southern Illinois and 

 from the base of the Isabel Sandstone in 

 western Illinois to the base of the Anvil 

 Rock Sandstone. The group, up to 400 feet 

 thick (Cady, 1952) , contains more promi- 

 nent marine limestone than does the Trade- 

 water Group and exhibits a more regular 

 cyclic alternation of beds. Some of the coals 

 are extensive; Colchester (No. 2) , No. 5, 

 and Herrin (No. 6) Coals are the commer- 

 cially important coals of Illinois. The 

 Summum (No. 4) Coal is less extensive 

 and the Briar Hill (No. 5a) Coal is re- 

 stricted essentially to southeastern Illinois 

 (Kosanke, 1950) . 



The Carbondale Group is considered 

 generally equivalent to the middle third 

 of the Desmoinesian Series of the Mid- 

 continent region, to the middle portion of 

 the Allegheny Series of the Appalachian re- 

 gion (Wanless, 1955) , and to the West- 

 phalian D, at least in part, of Europe 

 (Kremp, 1955) . At least the upper part of 

 the group contains the flora of zone 7 (Zone 



