GENUS ILLINITES GEN. NOV. 



51 



La Salle coal bed, Bureau County, Illinois. 

 Discussion. — This species in overall ap- 

 pearance resembles the megaspore species 

 Triletes fulgens Zerndt, 1937 ; however, it 

 is less than one third the minimum size 

 range of Zerndt's species, and it has a rela- 

 tively thin wall for a megaspore. Also 

 Zerndt's illustration (1937) lacks the lip 

 development so characteristic of Cadiospora 

 magna sp. nov. 



GENUS Illinites gen. nov. 

 Plate 1, figures 1-4 



The generic name Illinites is here pro- 

 posed for prepollens of the following 

 character: Grains have radial body sym- 

 metry, and an overall shape which viewed 

 proximally or distally is oval to elliptical 

 owing to two oppositely placed bladders. 

 Trilete mark is distinct and is on the proxi- 

 mal surface, which appears to lack a clearly 

 defined cap or exine. The trilete mark is 

 functional and not vestigial. The bladders 

 are not inclined distally as in Pityosporites 

 or modern pollen, and are as wide as or 

 wider than the body. A false furrow or 

 sulcus is the result of the bladder's over- 

 lapping the body of the grain. The known 

 size range in the longest diameter is 56 to 

 70 microns. The known body ornamenta- 

 tion is levigate or granulose and the bladders 

 are levigate externally and coarsely punc- 

 tate to reticulate internally. The pre- 

 pollens are probably of gymnospermic ori- 

 gin. 



Gymnospermic prepollens with func- 

 tional triradiate apertures represent a transi- 

 tional stage between the trilete vascular 

 spores and pollen tube development in 

 modern conifer pollen. For this reason, 

 and because the bladders do not appear to be 

 inclined distally and lack furrows, a new 

 genus is established. In an earlier publica- 

 tion, Kosanke (1947) considered the pollen 

 in question to be members of the genus 

 Pityosporites, which now seems un- 

 appropriate. The early pollens present in 

 Pennsylvanian deposits may prove of great 

 help in understanding climatic conditions. 

 Although they do not appear in abun- 



dance, they should receive proper taxonomic 

 treatment. 



Pityosporites has been considered indica- 

 tive of xerophytic upland flora. The 

 similarity of Pityosporites and Illinites 

 suggests that the latter may be associated 

 with xerophytic climatic conditions. If so, 

 the geographic location of uplands in or 

 adjacent to Illinois presents a problem. 

 Pennsylvanian uplands in this area are 

 thought to have existed in the Ozarks and 

 Kansas. The winged nature of Illinites 

 gen. nov. is an adaptation for wind dis- 

 persal, and since the genus is rarely present, 

 it is suggested that its origin may have been 

 somewhat removed from the place of deposi- 

 tion. 



Illinites unicus sp. nov. 

 Plate 1, figures 3-4 



Description. — The body of the grain has 

 a triradial symmetry which appears bilateral 

 because of two bladders arranged opposite 

 each other. The grains are compressed and 

 oval-shaped as viewed from either proximal 

 or distal side. The body is round to oval, 

 being oval at right angles to the transverse 

 plane. The bladders almost encircle the 

 body but are not much broader than the 

 body in a transverse plane. The genotype 

 (in the longest diameter) measures 63 mi- 

 crons, and at right angles to this measure- 

 ment, 42 microns. The body measures 32.5 

 X 42 microns, and the bladders overlap all 

 but 16.8 microns of the body at the center 

 of the proximal and distal sides. The 

 known size variance in the longest diameter 

 is 56 to 70 microns. The body of the 

 grain is finely granulose, and the bladders 

 are levigate externally and the internal 

 bladder ornamentation is finely reticulate. 

 The trilete mark is distinct, and the rays 

 measure 10 to 12 microns in length. The 

 pollen coat is less than 2 microns thick, 

 and the bladders are thin except where 

 thickened by internal reticulations. There 

 seems little doubt but that this species is re- 

 lated to the coniferous pollen. 



Genotype. — Maceration 494 Slide 15, 

 10-inch coal bed exposed in Coffee Creek, 

 Wabash County, Illinois. This horizon 



