SUBCARBOISIFI3EOUS PERIOD. 79 



CHAPTER VI, 



CARBONIFEROUS AGE. 

 SUBOARBONIPEROLTS PERIOD. 



EADIATA. 



Class ACTINOZOA. 



Order ZO A NTH ARIA. 



Family FAVOSITID^. 



Genus FAVOSITES Lamarck, 1816. 



Favosites divergens White and Whitfield. 



Plato V, fig. 4. 



Favosites White and Whitfield, 1862, Proc. Boston Soc. Nat. Hist., viii, 306. 



Favosites divergens White and Whitfield, 1862 (manuscript). 

 Favosites divergens Winchell, 1865, Proc. Acad. Nat. Sci. Phila., 112. 

 Favosites WUtfieldi White, 1874, Exp. & Surv. west 100th Merid., Prelim. Eep. Invert. 

 Foss., 15. 



Coral irreg'ularly flattened-convex or subhemispherical; cells abmjotly 

 diverging from the base, increasing interstitially ; apertures unequal in size, 

 the smaller ones being those of beginning interstitial cells; vertical walls 

 comparatively strong; diaphragms thin, about three within a space equal 

 to the diameter of a cell. Diameter of cells from two to three millimeters. 



The only specimen which the collection contains is silicified and partly 

 imbedded in limestone, so that the finer details of structure have been 

 obscured; but it is sufficiently perfect to indicate with little or no doubt its 

 identity with F. divergens. So far as I am aware, no other species of this 

 genus has been discovered in the Subcarboniferous rocks of North America, 

 nor in any rocks of later than Devonian age. This statement is made upon 

 the supposition that Favosites f mancus Winchell from the Goniatite lime- 

 stone of Indiana is not a true Favosites. The type-specimens of this species 

 were obtained from the Subcarboniferovis strata at Burlington, Iowa, where 



