FISTULIPORA. 



(Page 559.) 

 The following figures are given to show the character of the cell 

 apertures : 



Fig. 11. Mstulipora triloba. 



Lower Helderberg group. N'ew York. 

 Fig. 12. Fistulipora pustulosa. 

 Fig. 13. Fistulipora operculata. 



Hamilton group. N'ew York. 



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