INTRODUCTION. 23 



New Jersey Cretaceous, Berry, who has made a careful study of 

 its flora, writes as follows 1 : 



"While my work has been more in the nature of a reconnaisance, and not 

 sufficiently detailed for more than tentative conclusions, it would indicate that 

 the Amboy stoneware clay proper marks the upper limit of the Raritan. 

 This reduces the Raritan to a more orderly sequence by simply taking out the 

 variable members that overlie the very much eroded surface of this Amboy 

 stoneware clay. These lower Magothy members, which would then include 

 the laminated sands, are in one place a dark clay, which, within a short 

 distance, may thin out and be replaced by a sugary, somewhat ironstained 

 sand." 



Another point in the stratigraphy of this region where there 

 have been differences of opinion is in the relationships of the 

 Mount Laurel sand of Clark and the Wenonah sand of Knapp. 

 Clark recognized at Atlantic Highlands 2 about 5 feet of Mount 

 Laurel sand which was said to increase in thickness to the south 

 to fully 80 feet in the vicinity of Salem. At Atlantic Highlands 

 this formation is essentially the equivalent of Cook's "sand marl" 

 division of the "Lower Marl," and its faunal characters ally it 

 intimately with the overlying marl bed, while in Gloucester and 

 Salem counties it was essentially the whole of Knapp's Wenonah. 

 This bed was considered by Clark as a subordinate division of 

 his Monmouth formation. 



The name Wenonah was given by Knapp to the entire sand- 

 filled interval between the "Lower Marl" and the Marshalltown. 

 At Atlantic Highlands the formation comprised 30 or more 

 feet, including the whole of Clark's Mount Laurel sand and the 

 upper t portion of his Hazlet sand. To the south the formation 

 thickens and is essentially equivalent with Clark's Mount Laurel. 

 It is seten then that the lower boundary of the Clark's Mount Laurel 

 is, in fact, a line running diagonally across Knapp's Wenonah 

 from; near its top at Atlantic Highlands to near its base in the 

 vicinity of Salem, and that the two names are not equivalent. 

 For the correct interpretation of this portion of the section it has 

 been necessary to appeal to paleontologic evidence. There is 

 introduced at about this horizon a peculiar, foreign faunal ele- 

 ment which can be recognized more or less continuously across 



1 Geol. Surv. N. J., Ann. Rep. State Geol. for 1905, p. 136. 



2 Geol. Surv. N. J., Ann. Rept. State Geol. for 1897, p. 183. 



