Trans. N. Y. Ac. Set. 10 Oct. 23, 



layers of the Upper Bed, which are supposed to belong to the Eocene 

 Tertiary. 



The strike of the marl outcrops is about S. 55° W., and these crop- 

 pings extend from the Highlands of Navesink and Deal Beach on the 

 Atlantic coast, to the head of Delaware Bay, the outcrops of the beds 

 running in a general way parallel with each other. The Lower and 

 Middle Beds outcrop at pomts throughout this entire distance of one 

 hundred miles, while the Upper Bed croppings are not found further 

 southwest than Clementon, about sixty miles from Deal Beach. 

 Beyond this place the Upper Bed does not come to the surface and 

 is not known to exist. 



The strata dip toward the southeast about thirty feet to the mile. 



The Lower Marl Bed. 



This bed rests on strata of laminated sands, which compose the 

 upper layers of the deposits called the " Clay Marls," from the 

 nature of the rr.aterials of which they are constituted. These clay 

 marls contain numerous fossils ; but few openings have been made on 

 them, as the material is less valuable for fertilizing purposes than the 

 greensand marls occurring higher in the series. The component 

 layers of the Lower Bed are : (i), two to four feet of sandy marl, 

 containing a small percentage of greensand ; (2), twelve to sixteen 

 feet of blue marl, with much greensand and considerable carbonate 

 of lime ; and (3), a layer of about ten feet of clay and marl mixed, 

 which shades off into (2), the upper part of (3) containing little green- 

 sand. Much sulphate of iron occurs in the upper layer, often render- 

 ing the marl very astringent. 



One of the prominent features of this bed is the "shell layer." 

 This stratum is about half-way through the blue marl (2), and is 

 almost entirely made up of shells of Grypho'a vesicular is, Cav. It 

 varies from six to fourteen inches in thickness and extends entirely 

 across the State. The shells are generally large — many of them 

 six or eight inches across, frequently even larger — the convex valve 

 commonly well preserved, the flat one mostly imperfect. The marl 

 which underlies this "shell layer" contains the rarer fossils of the 

 bed, mostly as casts, the substance of their shells being very gener- 

 ally removed. Above the shell layer are most of the more common 

 fossils, whose shells are generally preserved. Among these are 

 Exogyra costata, Say ; Ostrea larva. Lam. (most abundant in the 

 clay and marl layer (3) ; Terebratella plicata, Say ; Belem7iitella mu- 

 cronata, Schloth (the phragmocones of this species are abundant at 

 some localities) ; and Neithca Mortoni, D'Orb. (abundant in frag- 

 ments). Under the Gryphcea layer occur most of the other fossils 



