EXPLANATION OF PLATE 7. 



Fig. 1. Pal.kaster granti (Spencer), p. 53. Natural size. 

 Fig. 2. Fenestella bicornis (Spencer), p. .55 



'la. Magnified, showing relative sizes of branches and interspaces. 

 Fig. 3. Rhinopora venosa (Spencer), p. ,54. 

 Fig. 4. ClathroporaC?) gracilis (Spencer), p. 54. 

 Fig. 5. POLYPORA (Fenestella) albionensis (Spencer), p. 55. 



5a. Fragment, magnified, showing the spaces betwe n the branches. 

 Fig. G, Pleurotomaria clipeiformis (Spencer), p. 57. Surface 

 view. 



6a. Side view of same. 

 Fie. 7. Orthoceras bartonense, p. 60. 

 Fig. 8. Cyrtoceras reversum, 60. 

 Fig. 9. Lituites niagarensis, 60. 



