90 EOCENE AND LOWER OLIGOCENE CORAL FAUNAS. 



developed, making 12, between wliicli, in the intercostal fniTows, are double 

 rows of perforations. The 12-costal condition exists for about 1..5 mm. from 

 the base, when 12 additional oostse are introduced. The costae on the basal 

 portion of the corallum are very slightly larger than those on the upper 

 portion; thev are not so prominent on the basal jiortion as in Turbinolia 

 pharetra. In tlie extreme upper portion 24 rudimentary costse are intro- 

 duced, making the total number 48 — -twice as many costae as septa. In the 

 intercostal furrows, after the development of the rudimentary costae there 

 are only single rows of perforations; during the 24-costal stage there are 

 double rows of alternating perforations in the intercostal furrows. The 

 septa are 24 in number, in three cycles. Those of the third cycle fuse, about 

 halfway between the corallum wall and the columella, Ijy their margins to 

 tlie sides of those of the first cycle. Their sides are beset with distant, 

 sharp, small spines. The septa are thin and weak. Columella ends in a 

 small, slender, hexagonal style. Height, 6.5 mm. ; diameter of calice, 3 mm. 



Localities. — Potomac Creek, Virginia; Pojjes Creek, Maryland. 



Geologic occurrence. — Pamuukcy foHuation, Aquia Creek beds. 



Type. — Johns Hopkins University. 



The crenate character of the costae distinguish this species from the 

 other Eocene Turljinolia- witli rudimentarv costae. 



Turbinolia claiijornensis sp. nov. 

 PI. VI, fig. U to 1Gb. 



Corallum small, conical, witli acute delicate costae, the margins of 

 which are entire. Around the calice there are 48 costn?, 24 correspond to 

 septa, and as many are rudimentary. The rudimentary costae are initiated 

 about 3 i mm. from the base. The costae of the first and second cycles are very 

 slightly enlarged near the base of the corallum. Tliere are three complete 

 cycles of septa. Their surfaces are covered with distinct conical spines. 

 The primary septa reach and fuse to the columella. The upper termination 

 of the columella is not a star, but compressed, a little excavated on the sides 

 below the up})er surface, and slightly granulate. Height of corallum, 5 mm. ; 

 diameter, 3 mm. 



Locality. — ( "hiibome, Alabama. 



