12 



ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 463 



TABLE 2 - COMPARISON OF THE SPECIES OF MYRIOTHECA (FROM DIFFERENT 

 SOURCES CITED IN TEXT) 







No. of 

















spo- 















Size of 



rangia 











Size of 





sporangi- 



per 







Conti- 





spores 



Myriotheca 



um (mm) 



pinnule 



Age 





nent 



Spore genus 



(Hm) 





desaillyi 



0.25 



50 



Westphalian 



C 



Eur. 



(verruca te exine) 



(unknown) 



scaberrima 



0.4 



40-50 



Westphalian 



D 



N.Am. 



Camptotriletes 



23-35 



monomakhof f i 



0.75 



30 



Westphalian 



C 



Eur. 



(unknown) 



(unknown) 



anglica 



0.5-0.75 



20 



Westphalian 



B 



Eur. 



? Punctatisporites 



70-82 



arnoldi 



1.0-1.4 

 0.5 



35 



(un- 

 known) 



Westphalian 



Autunian 

 (Permian) 



D 



N.Am. 

 Eur. 



Punctatisporites 

 (unknown) 



71-91 

 (unknown) 



permica 





which includes M. anglica Kidston, 1923, JVL arnoldi sp. nov. (p. 15), JVL permica 

 Remy, 1954, and probably JVL monomakhoffi Danz6, 1956, is characterized by 

 large sporangia (0.5 to 1.4 mm), 30 sporangia per pinnule, and large, circular, 

 smooth spores (70 to 90 \xm) . In the future it might become necessary to distinguish 

 these two groups as subgenera or separate genera. 



Myriotheca has been considered a microspore-bearing pteridosperm struc- 

 ture by Kidston (1923) and a fern fructification by Remy (1954) and Danze (1956). 

 The spores appear to be fern-like, but the systematic position of Myriotheca re- 

 mains unsettled. 



Myriotheca scaberrima (Lesquereux, 1870) Sellards, 1902 

 pi. 5, figs. 1-7 



1870 Sphenopteris scaberrima Lesquereux, p. 408; pi. 15, figs. 1, 2. 

 1902 Myriotheca scaberrima (Lesquereux) Sellards, p. 199, pi. 7, figs. 



5, 5a-c. 

 1958 Myriotheca scaberrima (Lesquereux) in. Langford, p. 277, fig. 508. 



Specimens: ISM 15728a, b (Langford Coll.) 

 PP 2575 

 PP 4759 



Description.— The frond is quadripinnate and has triangular-shaped lami- 

 nate pinnules which are up to 5 mm long and 2.5 mm wide and which are attached 

 along the broad bases. Larger pinnules are lobed, somewhat constricted basally, 

 and completely covered by sporangia on the abaxial side. There are 4 to 5 pin- 

 nules on each side of the pinnae. Pinnae are up to 14 mm long and 9 mm wide. 

 The pinna axis is 0.6 mm wide, striate, and flexuous. Two ridges can be seen on 

 the axis but only near the base. 



