72 PROCEEDINGS OF THE ACADEMY OP 



stone, or Orbitolite limestone, eighty feet ; 4. Vicksburg group, with a new 

 species of Orbitolite, N. sup era, Conrad. 



This formation appears at Cape Sable, near Annapolis, where, at about the 

 water level, "under a stratum of sand, and resting upon an impermeable 

 crust of ferruginous sandstone, lies imbedded in a layer of almost pure alu- 

 mine, a forest of pine trees, thrown down by some ancient convulsion. The 

 crust which forms the base of this aluminous layer is a little below the level 

 of low tides and is of considerable hardness. The imbedded pines are con- 

 verted into lignites more or less impregnated with sulphuret of iron. The 

 central parts are generally transformed into pure metallic sulphuret, some- 

 times exhibiting in the hollow parts octohedral crystals of a yellowish metal- 

 lic lustre and great hardness. The more remote the ligneous layers from the 

 centre, the less they are saturated with sulphuret of iron. The external rays, 

 as well as the cortical layers, are generally pure lignite, some compact and 

 black, others retaining the color and friability of rotten wood. In some in- 

 stances their texture seems to have suffered but little alteration : the central 

 system, concentric rays, the bark and knots being perfectly discernible ; even 

 fruits are occasionally found in a pretty good state of preservation as to 

 form."* The lignite is correctly placed in Morton's diagram as overlying 

 the secondary marls. In Morton's paper the first published notice of the for- 

 mation appeared, drawn up from the notes of Lardner Vanuxem, who was 

 familiar with the strata in South Carolina. 



Deshayes states that he has found no species of organic remains common 

 to cretaceous and eocene strata in Europe or Asia, and I have no doubt that 

 the destruction of life was total over the whole surface of the globe at the 

 close of the cretaceous era. Deshayes, indeed, affirms that life has been fi\*p 

 times destroyed and renewed in the past history of the earth. When we find 

 evidence of surprising changes of level in the eocene period, the limited na- 

 ture of a mixed fauna is remarkable, for we would expect to find it much 

 more extensive at the base of the eocene. The bed of the Atlantic along the 

 coast of the United States, from Cape May to the Gulf of Mexico, contains a 

 mixture of recent and miocene shells, which, if elevated above the sea level 

 would present a group of shells consisting of recent and extinct species, so like 

 in preservation that the fossil could not be distinguished from the recent forms, 

 except by one conversant with all the miocene shells. 



Deshayes affirms of the Maestrich beds, " that there has been an accidental 

 mixture of cretaceous and eocene ; a degradation of a stratum of fossilliferons 

 marl diluted in the bed of the tertiary sea at the time of the first deposit. 

 The bed of the ocean, under our own eyes, shows an accidental mixture of 

 this nature." 



The Wilmington rock proves conclusively that this was the case in North 

 Carolina. Eocene and cretaceous fossils are there mingled in a breccia. When 

 I first saw this rock in 1832, no fracture or excavation revealed its true cha- 

 racter ; but the external resemblance to the Timber Creek limestone of New 

 Jersey, with its corallines, was striking. The mixture of secondary aDd 

 tertiary species in this breccia, shows ti.at a disturbance occurred in the bed 

 of the eocene ocean, which evidently, from Tuomey's account, extended into 

 South Carolina. No one, I suppose, will tell us that the Venericardia plani- 

 costa existed iu the cretaceous period, yet countless thousands may be ob- 

 served at the base of the eocene. It is true that in Europe a series of strata, 

 termed Upper and Lower Landenien and Heersien, are said to intervene be- 

 tween the chalk and eocene ; but one of the characteristic fossils of the Upper 

 Landenien occurs in the Shark River beds, the Cyprina Morrissi, of Sowerby. 

 It is therefore probable that the former system is merely an extension of the 

 London Clay. Certainly, in the United States, there is no such system as the 



* Durand, Joum. Phila. College of Pharmacy, v. 12, 1834. 



[April, 



