98 



EOCENE AND LOWER OLIGOCENE CORAL FAUNAS. 



logically, outward). The rows of granules on opposite faces of a septum 

 are opposite, and when the edge of a septum is viewed from above they 

 give the appearance of striations extending down the sides of the septum 

 and across its margin. Around the fossa the margins are entire, but 

 external to the fost.a they are gently and finely crenate. In the region of 

 the wall the septa are much thicker, and there are many minute granules 

 along the edges and free portions. Pali before all cycles of septa except 

 the last; small, with rounded upper margins, sides granulate. Columella 

 fascicular. 



Greater diameter of calici 

 Leaser diiimeter of calice 

 Heislit of corallum 



1 



Mm. 



11.75 



11.5 



3.5 



Mm. 



10. 75 

 9.75 

 3.5 



Mm.. 

 9. 75 

 9 

 4 



Locality. — 8ix milcs west of Desoto Station, Clarke County, Mississippi. 

 (F. Burns, collector.) 



Geologic occurrence. — Lower Claibome. 



Types. — United States National Museum. 



The only closely related species is Tr. Iinmlitiformis. Tr. depressus is 

 easily recognized by its more irregular transverse outline and its more exca- 

 vated calicular fossa. 



Trochocyathus stantoni sp. nov. 

 PI. VII, figs. IS and 18a. 



Form discoid; base flat, with a scar in the center as if it were attaclied, 

 covered by epitheca which reaches to the calicular inargin. Twenty-four 

 costie of equal size ; apparently there are 24 smaller costiie alternating with 

 the large ones. Septa arched, projecting high above the flat base, side 

 granulated, margins slightly undulated transversely. T'he arrangement is 

 in four complete cycles of six systems, the total number being 48. Those 

 of the first, second, and third cycles of about the same size; the fourth cycle 

 smaller. Calicular fossa deep. Pali present, but the details could not be 

 made out. Character (jf the columella could not be ascertained. 



The measurements are: Diameter of l)ase, 14.25 mm.; height, 5.75 

 mm.; depth of calice, more than 2 nun. 



