FORAMINIFKKA FROM DEEP WELLS 39 



LOWER OLIGOCENE 



In a number of wells there are fragments of Lcpidocyclina that 

 may possibly be of Lower Oligocene age but they are not suf- 

 ficiently well preserved to admit of specific determination. There- 

 fore the Oligocene must be very questionably placed in any of 

 these wells except in that at Marathon where at 852 and 900 feet 

 there occurs the genus Hcterostcginoides which I have found in 

 the Oligocene of Panama and the West Indies. 



EOCENE 



The Upper Eocene represented by the Ocala Limestone can now 

 be very definitely placed in a number of wells. The four species — 

 Lepidocydina ocalana, L. pscudomarginata, L. pscudocarinata, and 

 L. floridana, together with Hcterostcgina ocalana, mark very defi- 

 nitely the facies of the Ocala Lijnestone which is developed in north 

 central Florida. The accompanying table shows the depth at which 

 these species occurred in a number of wells. There is no trace of 

 Orthophragmina or of the species of Lepidocydina and Opercidina 

 which are characteristic of the facies of the Ocala developed in 

 northern Florida and southern Georgia. As already noted in 

 the previous paper the Ocala Limestone seems very definitely 

 to be only about 40 feet thick in the various wells in which it 

 was found. Below the typical Ocala there occurs a horizon 

 characterized by a large species of Nummulitcs and this in turn 

 in one well — that of the Bonheur Development Company at 

 Burns, Wakulla County, has a horizon marked by numerous 

 specimens of Rotalia armata which, however, does not seem 

 to be developed in any of the other wells. 



\\\ the well at J\'I,arathon on Key Vaca there are a number of 

 rather large specimens which may be Comdites americana, or a re- 

 lated species. C. americana is known from the Eocene of St. 

 Bartholomew, Leeward Islands, Haiti, Cuba and Panama. These 

 specimens in the Marathon Well mav therefore represent an Eo- 

 cene horizon below that marked by the Lepidocydina. The well is 

 not cased below the point at which these appear, therefore this ac- 

 tual point of occurrence is somewhat vague. It. however, does 

 represent an Eocene which is apparently typical of Panama and the 

 West Indies, and unlike that of northern Florida. 



