2S6b THE DAWN OF LIFE. 



{a) Perforata — having calcareous skeletons penetrated with 

 pores. 



(&) Imperforata — having calcareous, membranous, or arena- 

 ceous skeletons, without pores. 



The place of Eozoon will be in the higher sub-order, 

 Perforata. 



TV. The sub-order Perforata includes three families — the 

 NummulinidcB, Glohigerinidce, and Lagemdoe. Of these Car- 

 penter regards the Nummulinidae as the highest in rank. 



The place of Eozoon will be in the family NummulinidcB, or 

 between this and the next family. This oldest known Proto- 

 zoon would thus belong to the highest family in the highest 

 sub-order of the lowest class of animals. 



