PLATE 73. 



Fig. 1. 515. 1. Favosites n:agarensis? ( Pag. 3,94.) 



1 a. A fragment of stone, showng one mass in its natural position, while the other is reversed. 



\ b. A. surface showing the ends of the columns. 



1 c. A broken snrfiice, showing the cellular structnre : the walls and dissepiments are covered by fine quartz 



crystals. 

 \ d. A small mass of this species. 



1 e. A polished surface of another smaller specimen 



Fig. 2. 523. 1. Stromatopora concentrica. (Pag. 325.) 



2 & 2 a, b. Indvidual masses of various forms. 



