LIST OF ILLTrSTRATIONS. 



FIG. 



53. Slu'll oi Fti'urofuinaritt . 



54'. A Pentaci'inid 



55. Skeleton of Novtlieru Sea-Con" 



50. Leaf JButtei-llv . 



57. Test of Commou Sea-Urcliiu 



58. Te.st of Sceoudary Sea-Urchiii 



59. Test of Palivozoic Sea-Urcliin 



60. Test of Cretaceous ITeai-t-Ureliiii 

 (U, .V Xuiuiiuilite 



02. Flint Tnipleuient 



0:-!. Cone ol' Flint 



PAUE. 



154 

 15S 

 lOS 

 17S 

 180 

 189 

 190 

 191 

 197 

 210 

 212 



