PLATE VII. 



Laciniate specimens of Orhitolites complanata. 



All the disks represented in this Plate are magnified four diameters ; and, with the 

 exception of fig. 3 (which represents a normal disk of the massive t}-pe), show in a 

 greater or less degree the " laciniation " of margin, which seems to depend — hke the irre- 

 gular outgrowths from the central and intermediate portions — on an excess of productive 

 power. 



Figs. 4 a and 4 h show, under a higher power, the central and ouc of the intermediate 

 outgrowths seen in fig. 4, so as to i^xhibit the pores which coiTespond to the marginal 

 pores of the regular annuli. 



