328 DlCTYOSPON<JID.«. 



PLATE LXV. 

 PIIRAGMODICTYA, Hall. 



Page 172. 

 (See Plates LXIV, LXVI, LXVII, LXVIII.) 



Phbaomodictya catillifoemis, Whitfield (sp.). 



Pago 173. 

 (See Plates LXIV, LXVI, LXVII, LXVIII.) 



Figure 1. The lower side of a large basal disc with the entire periloph 

 retained ; showing the fine radial spicular striations of the former 

 and the ridged surface and somewhat irregular margin of the latter 



Figure 2. A natural half section of a basal disc with a highly elliptical form, 

 undoubtedly due to lateral compression. 

 Keokuk group. Crawfordsville, Indiana. 



PlIUAGMODICTYA PATKLLIFORMIS, Hall. 

 Page 176. 



Figure 3. The lower surface of a large basal disc with a highly eccentric 

 apex. 



Keokuk group. From the sandy calcareous layei^s overlyitig tlie 

 calcareous shales, at GraiofordsviUs, Indiana. 



