163 MURFREESBORO STAGE — OLSSON II 



At Alum Bluff, Miocene beds are exposed overlying uncom- 

 formably the Upper Oligocene. The contained fauna is strictly 

 a southward extension of the Chesapeake and not of the nearer 

 and warmer Duplin Miocene. Lithologically, the beds consist 

 of blue or gray sands and are characterized by an abundant mol- 

 luscan fauna of which the following species are noteworthy and 

 of value for correlation. 



Mulina congesta is the commonest fossil (range Murfreesboro- 

 Pliocene), Ostrea disparilis ( Murfreesboro- Yorktown and Duplin), 

 Cardium virginianum (Murfreesboro), Pecten eboreus (Murfrees- 

 boro-Pliocene), Ecphora quadricostata (St. Mary's- Yorktown), 

 Busycon maximum (Murfreesboro-Pliocene). These beds there- 

 fore correlate very well with the Murfreesboro of Virginia and 

 North Carolina. 



In South Carolina, Miocene is known to occur at several lo- 

 calities and available evidence indicates that two horizons or 

 stages are represented. Since the appearance in 1857 of Tuomey 

 and Holmes work on the Miocene and Pliocene faunas of that 

 state, comparatively little has been done, so that the distribution 

 of the Miocene faunas is known only in a general way. In an 

 earlier paragraph the geological range and distribution of Ec- 

 phora quadricostata was considered and shown to be a cold water 

 or Chesapeake species and lacking from the warmer Duplin beds. 

 Its range is St. Mary's to the Yorktown. In South Carolina, 

 Ecphora quadricostata is recorded by Tuomey and Holmes from 

 the Miocene of the Pee Dee river. The age is therefore either 

 St. Mary's or Murfreesboro, more probably the latter. 



