PLAT E XXIV. 



Fig. I. Upper specimen, Dendropora alternans. Hamilton group, Thunder 

 Bay, 

 Specimen at the base, Dendropora reticulata. Hamilton group. Par- 

 tridge Point. 



2. Upper specimen, Striatopora Huronensis. Niagaragroup, Point Detour. 

 Lower left-hand specimen, Striatopora rugosa. Hamilton group. 



Thunder Bay 

 Lower right-hand specimen, Dendropora ornata, juvenile specimen. 

 Thunder Bay, Hamilton group. 



3. Upper group of specimens, Vermipora fasciculata. Corniferous lime- 



stone and Hamilton group. Magnified 2 diameters. 

 Lowei three stems, Vermipora Niagarensis. Niagara group, Iowa. 

 Magnified 2 diameters. 



4. Upper row of stems, Dendropora reticulata. Magnified 2 diameters. 



Thunder Bay. 

 Lower group of stems, Dendropora] proboscidalis. Hamilton group. 

 Thunder Bay 



