54 



ILLINOIS STATE GEOLOGICAL SURVEY 



Discussion. — The above description of 

 the fertile and abortive megaspores found 

 in Illinois coals agrees remarkably well 

 with that recently given by Dijkstra 

 (1955c). His paper should be consulted for 

 the listing of synonyms, discussion of the 

 various aspects of spore morphology, and 

 his reasons for interpreting this species as 

 a species of Cystosporites. 



The granulater material adhering to the 

 distal portion of the fertile megaspores is 

 considered by Dijkstra (1955c), Chaloner 

 (1954a), and Arnold (1950) as analogous 

 to the "wing-like appendage" or "stalk" de- 

 scribed by Bochenski (1936) as attaching 

 the fertile megaspore (Cystosporites gigan- 

 teus-type) to the adaxial wall of the spo- 

 rangium of Lepidostrobus major. A similar 

 mode of attachment was noted by Chaloner 

 (1954a) in the sporangia of L. monospora. 

 In this study I noted not only the common 

 occurrence of this appendage on fertile 

 spores of C. verrucosus but also its occur- 

 rence on several specimens referable to C. 

 giganteus. 



The spore coat of an individual fertile 

 megaspore of Cystosporites verrucosus may 

 vary from a dense fibrous mesh, having 

 gross fibers and small interstices, to a granu- 

 lose-appearing coat. The mesh is most 

 dense or the coat most granulose in the api- 

 cal region. Coats of the abortive spores ap- 

 pear granulose. Coats with the very dense 

 mesh structure (pi. 11, fig. 8), bear a marked 

 resemblance to the coats of some lagenicu- 

 late spores. 



Dijkstra (1955c) found, as I have, that 

 the fertile spores of Cystosporites verru- 

 cosus possess a fibrous coat, at least in the 

 central region of the saclike spore body. 

 This fibrous type of coat is a characteristic 

 feature of the genus Cystosporites (Schopf, 

 Wilson, and Bentall, 1944, p. 41). In the 

 original descriptions of Lagenicula saccata 

 Arnold, 1950, and of the spores Lepidostro- 

 bus monospora Chaloner, 1954, the spore 

 coats were described as granular. However, 

 as Dijkstra (1955c) pointed out, high mag- 

 nification study by transmitted light is 

 usually necessary to distinguish the fibrous 

 nature of the spore coat of C. verrucosus. 

 In Dijkstra's opinion the spores of Lepi- 



dostrobus braidwoodensis Arnold, 1938, 

 and Lepidostrobus monospora Chaloner 

 1954, and Lagenicula saccata Arnold, 1950, 

 are all comparable to Cystosporites. 



Cystosporites verrucosus and C. verruco- 

 sus-type spores have been reported (Dijk- 

 stra, 1955c) from Belgium, Netherlands- 

 Westphalian A, B; Great Britain - West- 

 phalian B (Lepidostrobus monospora) ; 

 Spain - Westphalian A; U.S.A. (Michi- 

 gan) - Westphalian A, B; U. S. A. (Illi- 

 nois) - shale above Colchester (No. 2) Coal, 

 lower Carbondale - Westphalian D? (L. 

 braidwoodensis) . 



The spores of this species are not very 

 abundant in Illinois coals but their frag- 

 ments are readily identifiable because of 

 the characteristically folded, dense- 

 ly meshed spinose coat. 



Occurrence. — Spores of this species are 

 rare in the "Makanda" Coals (macerations 

 905, 907) , present in the Pope Creek Coal 

 (maceration 916), rare to common in the 

 Colchester (No. 2) Coal (macerations 824, 

 825, 826) , and present in the Indiana Coal 

 IV (maceration 881) . Thus, Cystosporites 

 verrucosus is represented by sporadic occur- 

 rences in coals of the Caseyville, Trade- 

 water, and Carbondale Groups. 



Genus Spencerisporites Chaloner, 1951 



Type species. — Spencerisporites radiatus (Ibrahim) 

 n. comb. [Spencerisporites karczewskii (/emdt, 

 1934, pi. XXXI, fig. 3) Chaloner, 1951], by 

 designation of Chaloner, 1951, p. 862. 



Discussion. — The spores of Spencerispo- 

 rites, although small (generally 300 to 400 

 n) for "large" spores, have a distinctive as- 

 pect. The more or less spherical spore body 

 is encircled at the equator by a bladder 

 which is subtriangular or deltoid-shaped in 

 proximo-distal outline and possesses a mar- 

 ginal frill or flange. The spores commonly 

 have strongly developed trilete rays and 

 some are characteristically ornamented 

 with radial striations on the contact areas. 



The correct generic designation for these 

 spores, found isolated, is somewhat in 

 question. Similar spores were first described 

 from a lycopod cone designated as Lepido- 

 strobus by Williamson (1879, 1894) which 

 Scott (1898) later redescribed and desig- 



