FAUNA OF THE CLIFFWOOD CLAYS 335 



cliffivoodensis and Pteria petrosa, have nowhere been observed in the 

 Woodbury fauna. 



It is unnecessary to make comparison between the Cliffwood and 

 the Marshalltown faunas, as there is scarcely anything in common 

 between them ; but with the fauna of the Wenonah sand the Cliffwood 

 fauna has more in common even than with that of the Woodbury clay. 

 Among the species listed in the table given above, it will be seen that 

 fourteen species are recorded as being common to the Cliffwood and 

 the Wenonah, eleven to the Cliffwood and the Woodbury, and only 

 ten to the Cliffwood and the Merchantville. These numbers do not 

 fully express the relative proximity of relationship between these 

 several faunas, although they do partially, because no account is 

 taken of the relative abundance of the forms noted. As a matter of 

 fact, when the abundance of the different species in the different 

 faunas is taken into account, the similarity of the Cliffwood and Weno- 

 nah faunas is accentuated, while that between the Cliffwood and 

 the Merchantville is diminished. Aside from the crustaceans of 

 the Cliffwood fauna, the two species Pteria petrosa and Isocardia 

 cliffivoodensis are perhaps the most characteristic forms, and both 

 of these occur in the Wenonah fauna. Veleda lintea is another con- 

 spicuous Cliffwood species which occurs more frequently in the 

 Wenonah sand than in any other of the New Jersey Cretaceous 

 formations. 



It is believed that these comparisons which have been instituted 

 make clear the fact that, however much or however little the Cliff- 

 wood fauna has in common with the faunas of the higher formations, 

 it does have a unity of its own. Although many of the species occur 

 also in other horizons, the whole assemblage of species, considered 

 as a faunule, possesses characteristics which serve to distinguish it 

 from any of the other faunules with which it has been compared. 



The geographic distribution of this Cliffwood fauna differs notably 

 from that of the Merchantville, it being limited, so far as now known, 

 to a small area between Cliffwood Point and the head of Cheesquake 

 Creek. The distribution of the Merchantville fauna is entirely across 

 the state, from the south shore of Raritan Bay to the shores of Dela- 

 ware Bay; throughout its entire extent it is remarkably constant in 

 its characters, and the Merchantville beds are everywhere marked 



