THE UPPER CRETACEOUS OF NEW JERSEY 75 



other hand, Cyprimeria, Litcina cretacea, Breviarca, Cancellaria 

 subalta, and others which were rare or entirely absent from the Mer- 

 chantville, are the commonest species of the fauna. Furthermore, 

 this same faunal distinction between the two beds holds as sharply 

 in the region opposite Philadelphia as in Monmouth County. The 

 faunal lists of the Matawan, heretofore published, omit many of the 

 most abundant and widespread species of the Woodbury clay, and 

 are predominantly of Merchantville species, so that the Matawan 

 fauna as previously recorded is somewhat incomplete. 



The Columbus sand has as yet not yielded a single fossil, and is 

 perhaps entirely barren. The Marshalltown formation, however, 

 in its more southern extent is abundantly fossiliferous, although 

 in Monmouth County no fossils have yet been found. Near Swedes- 

 boro the fossils in this bed occur in a remarkably perfect state of 

 preservation and in great numbers. A large Trigonia, probably 

 T. mortoni, is represented by hundreds of individuals, and asso- 

 ciated with this species are Cyprimeria sp. and Idonearca vulgaris 

 in abundance. In this fauna the large and ponderous specimens 

 of Gryphaea vesicularis and Exogyra costata, with innumerable 

 specimens of a variety of Ostrea larva, are a conspicuous faunal 

 element for the first time, foreshadowing, perhaps, the Navesink 

 fauna. The whole complexion of the fauna is different from either 

 the Merchantville or the Woodbury, although certain species are 

 present which occur also in one or both of these lower faunas. 



Between the Marshalltown clay-marl and the "lower" or Navesink 

 marl there is a well-marked sand bed 40-60 feet thick. In Mon- 

 mouth County it is, on the whole, a fine micaceous sand, with some 

 clay laminae and locally near its base with thicker clay lenses. Locally 

 its upper portion is a coarser quartz sand, with a commingling of 

 glauconite near the marl bed. In the southern counties it is pre- 

 dominantly a coarse quartz sand with some disseminated glauconite, 

 the fine micaceous phase being inconspicuous or even perhaps 

 entirely absent. This formation Knapp called the Wenonah sand. 



In Monmouth County Clark's Hazlet sands correspond exactly 

 with Cook's "laminated sand," and almost exactly with Knapp's 

 three formations — the Columbus sand, Marshalltown clay-marl, and 

 the Wenonah sand — the upper few feet of the latter being apparently 



