1890.] XATUKAL .SCIEXCES OF PHILADELPHIA. 147 



The evidence as to the sections from .383 feet to 1225 feet, Avhere 

 the bottom of the very dark green marl bed is reached, is preponder- 

 atingly in favor of Miocene age for these strata. 



In view of the lack of distinctive Eocene fossils below that depth 

 the occurrence of Placocyathns and the still decided Miocene aspect 

 of the few molluscan remains, it may be concluded that the boring 

 has not yet passed through the Miocene. 



The occurrence of Turritella plebeia and Pecten Hwnphreysii in 

 these wells, and of Turritella plebeia in a well at Cape May Point at 

 a dejith of about 400 feet, would indicate for the u])per portion a 

 INIiddle INIiocene age, while all below would be Lower iNIiocene. 



Reference has already been made to the dip of the yellow gravel 

 and of the diatomaceous clays, the latter being placed at 23 to 24 

 feet per mile. The shell marl at Shiloh outcrops about 60 feet above 

 tide, and the distance between parallel lines of strike for Shiloh and 

 the well'i^ 35 miles. The bottom of what is probably the correspond- 

 ing shell stratum in the well is at 757 feet. A calculation ])ased on 

 these data gives 23 feet to the mile as the dip for the Shiloh beds. 



The water from Winslow well, and from Atlantic City Well No. 1 

 at 1100 feet, are of the same quality as proved by analysis. This favors 

 their being from the same stratum. Winslow is distant 30 miles and 

 the depth of the well thei-e below tide is 215 feet. Based on these figures 

 the dip of strata in that portion of the well is 29 to 30 feet per mile ; 

 this increase of dip is probal)ly correct. In fact when we take into 

 consideration the greater thickness seaward of the sands and clays 

 in the lower jiortions of the well, together with the oscillations of sea 

 level as shown by the character of the fossils, these being alternately 

 shallow sea and deep sea forms, it is quite likely we shall yet find a 

 still greater increase of dip for the base of the Miocene. 



The results of this examination indicate a greater thickness for 

 the Miocene deposits of the southern part of the State than has 

 generally been held by geologists, and as a consequence increases the 

 heretofore estimated dip of the underlying Cretaceous and Eocene 

 beds in that section of the State. 



These INIiocene shell and diatom l)eds are no doubt closely related 

 to beds of similar character and of the same age in Maryland and 

 Virginia. The author is not however at present able to trace any 

 one stratum continuously. The diatomaceous clays at Atlantic 

 City occur above beds containing Perna, while in the States just 

 named similar clays occur below Perna beds. That there are several 

 Perna beds would seem to be the solution of this problem. This 

 however remains vet to be demonstrated. 



