Illinois State Geological Survey 



Report oe Investigations No. 97 Plate 2 



PHYLLOTHECA 



sclerotheca 



cyathotheca 



stereotheca 



stereotheca 



palicolumella sclerocolumella stereocolumella acrocolumella cystocolumella 



11 ^..J.^^16 



axial complex primary septa 



protosepta 



protosepta protosepta, metasepta 



AND metasepta AND MINOR SEPTA 



23 ^^S>HC^-24 



APHROID THAMNASTRAEOID 



25] 



