34 



PENNSYLFANUN SPORES OF ILLINOIS 



mal and distal portions of the spore coat are 

 covered with large widely spaced papula- 

 tions. The equatorial portion of the spore 

 coat is thickest at the inner margins as 

 shown by its nearly opaque nature. At the 

 outer margin this portion is translucent. 

 There is a sharp contrast between the nearly 

 opaque and translucent portions. The 

 nearly opaque portion is irregular in out- 

 line due to its structure which is composed 

 of a number of small plicating sheets. The 

 trilete rays are faintly present and extend 

 into the thick equatorial portion of the spore 

 coat. The entire length of the rays, in- 

 cluding that portion extending into the 

 equatorial area, varies from 16 to 18 mi- 

 crons. As viewed transversely, the proximal 

 and distal walls of the spore coat are thin, 

 certainly less than 2 microns. The equa- 

 torial portion of the spore coat including 

 the nearly opaque and the translucent area 

 measures between 12.5 and 14.7 microns 

 on the holotype specimen. A direct trans- 

 verse measure of the holotype reveals that 

 more than 63 percent of the spore is the 

 equatorial portion of the spore coat. 



Holotype.— Maceration 520-A Slide 2, 

 Bald Hill coal bed, Williamson County, 

 Illinois. 



Denso-sporites triangularis sp. nov. 



Plate 7, figure 1 



Description. — Spores are radial, faintly 

 trilete, outline in transverse plane is sub- 

 triangular and lacking in folds although 

 some specimens show the equatorial area 

 compressed over a portion of the proximal 

 and distal portions of the spore coat. The 

 holotype measures 58.8 X 58.8 microns and 

 the known size range is from 52 to 65 mi- 

 crons. The proximal and distal areas of 

 the spore coat are granulose to vermiculate. 

 The thicker equatorial area is variously 

 ornamented. In part it is punctate and the 

 margin has a few spines at which point 

 the spore coat is translucent. Only faint 

 lines resembling the tetrad mark have been 

 observed. The proximal-distal portion of 

 the spore coat is thin, not over 2 microns in 

 thickness. The thicker equatorial portion 

 varies from 12.6 microns between the cor- 



ners to 18.9 microns at the corners. About 

 55 percent of the total spore coat is that of 

 the equatorial portion. 



Holotype. — Maceration 144 Slide 3, 

 "Sub-Babylon" coal bed, Fulton County, 

 Illinois. 



GENUS Cirratriradites Wilson and 

 Coe, 1940 



Plate 7, figures 3-6 



Cirratriradites is rarely abundant in Illi- 

 nois coal beds. The two known exceptions 

 are the coal beds between the Babylon and 

 Delwood coal beds of the Tradewater group 

 and No. 5 coal bed of the Carbondale group. 

 The known range is from the base of the 

 Tradewater (the Babylon coal bed) to 

 below No. 8 coal bed in the McLeansboro 

 group. The known range is not continuous, 

 since some of the coal beds within this range 

 appear to lack the genus. C. difformis and 

 C. rotatus, which are new species from the 

 Tradewater group, are of particular value 

 for correlation purposes because of their 

 abundance and restricted range. 



The following description of the genus 

 Cirratriradites is based on 14 established 

 species and four new species: spores are 

 radial, trilete, with a definite flange, orig- 

 inally roundly oblate and for this reason 

 when compressed only minor folds are evi- 

 dent. In transverse plane the spore body 

 is round to subtriangular and the flange 

 may be triangular, due to the extention of 

 the rays, or almost round. The known size 

 range is from 40 to 102 microns. The 

 ornamentation of the spore coat is levigate, 

 granulose, punctate, or reticulate. Some 

 species have distal ridges which may enclose 

 one to four or more areas in an unusual type 

 of ornamentation. The flange is frequently 

 radially striate and in some species the 

 flanges have radially arranged processes. 

 The trilete rays are usually strongly devel- 

 oped, as are the lips, whereas the commis- 

 sure is often sharply developed but thin. 

 As reported by Schopf, Wilson, and Bentall 

 (1944), the affinity of the spores of this 

 genus is unknown although they are thought 

 to be related to the lycopods. However, 

 known microspores of Lepidostrobus do not 



