50 



ILLINOIS STATE GEOLOGICAL SURVEY 



Lick Coal (maceration 151) , Orange Coun- 

 ty, Indiana. 



Genus Cystosporites Schopf, 1938 



Type Species. — Cystosporites breretonen- 

 sis Schopf, by his designation. 



Description. — The fertile spores are large, 

 some are up to more than 10 mm in length, 

 oval or saclike in outline; abortive spores 

 are smaller, circular to oval in outline. 

 Spores of this genus are fundamentally 

 radially symmetrical and trilete. Trilete 

 structures are well developed, but incon- 

 spicuous, on the fertile forms, because of 

 their small size relative to spore size. The 

 suture is distinct, and extends to well devel- 

 oped arcuate ridges. Lips in many speci- 

 mens are moderately developed and in some 

 specimens are elongate at apex. A spongy- 

 appearing apical cushion or tuft is present 

 on both fertile and abortive spores of two 

 species. Abortive spores have well devel- 

 oped trilete structures but details of con- 

 tact areas and sutures may be masked by 

 folding or by the apical cushion. Ornamen- 

 tation is variable. Spores of one species pos- 

 sess spines; those of another have closely 

 spaced, low, convex bumps. The spore coat 

 is characterized by a fibrous meshlike struc- 

 ture, generally best developed in medial 

 portions in fertile spores where the coat is 

 thinnest. Abortive spores generally have a 

 thick granulose-appearing coat. 



Affinity. — As far as is known, this genus 

 is inclusively correlative with the Lepido- 

 carpaceae (Bochenski, 1936; Schopf, 1938, 

 1941a; Chaloner, 1952; Schopf, Wilson, and 

 Bentall, 1944) . 



Occurrence. — Although one species has a 

 long stratigraphic range, represented both 

 in the upper Mississippian and Pennsyl- 

 vanian, most of the other presently recog- 

 nized species appear to be restricted to the 

 Pennsylvanian. Dijkstra (1957) recognized 

 one species from the Lower Carboniferous 

 of Egypt. 



Cystosporites breretonensis Schopf, 1938 

 Plate 12, figures 9-11 



1936 Triletes cf. T. giganteus Zerndt in Schopf 

 (1936a), fig. 5 (holotype of species, by desig- 

 nation of Schopf, 1938). 



1938 Cystosporites breretonensis Schopf (in part), 

 Cystosporites breretonensis forma reticulatus 

 Schopf, p. 40-42; pi. 1, fig. 11; pi. 7, fig. 4. 



Discussion. — Spores of Cystosporites bre- 

 retonensis apparently cannot be differenti- 

 ated from those of C. varius on the basis of 

 size, shape, or type of apical prominence, 

 but only on the possession of low, convex 

 bumps which cause an inverse reticulation 

 on the outer surface of the spore coat. The 

 holotype specimen is a large fertile spore 

 showing both a spongiose apical cushion 

 and an inverse reticulate coat in the apical 

 region. Attached to the fertile spore are two 

 abortive spores which also have a spongiose 

 apical cushion and an inverse reticulate 

 coat. The specimens illustrated (pi. 12, 

 figs. 9a, 9b, 9c) show the same features that 

 the holotype shows. 



It is important to note that fertile forms 

 of this species possess an apical cushion, as 

 do the fertile forms of Cystosporites varius, 

 and that whenever fertile and abortive spec- 

 imens are still attached, both possess inverse 

 reticulate coats. Although this ornamenta- 

 tion is usually developed over the entire sur- 

 face of the abortive spores, it is usually con- 

 fined to the proximal half, or less, of the 

 fertile spores. Spores of C. varius, with no 

 apparent inverse reticulation, are apt to oc- 

 cur with those of C. breretonensis. They 

 are not necessarily found together, nor do 

 they necessarily occur in equal numbers 

 when found together. 



In macerations 588, 580, and 520, abor- 

 tive spores are associated with strands of 

 spongiose material, loosely connected to the 

 spore body only at the radial extremities 

 and encircling the spores at the position of 

 the arcuate ridges. Some of these spores do 

 not have a well developed inverse reticula- 

 tion. 



The spores of Cystosporites breretonensis 

 are not easily distinguished from those of 

 C. varius by reflected light. On spores that 

 have an extremely well developed inverse 

 reticulation, as do some from Carbondale 

 coals (pi. 12, fig. 11) , the surface ornamen- 

 tation can be distinguished by reflected 

 light under a binocular microscope. The 

 ornamentation is not internal but occurs on 

 the outer spore coat surface, nor does it 



