1844.] . 301 



in a S. S. W. direction, across the olive plantation, and down a 

 gentle declivity, until it was lost sight of. 



The following is the mean of two analyses that were made of 

 the purest specimens of phosphorite that could be selected : — 



100-00 



The authors take occasion to remark that, in seven varieties of 

 Apatite which were analysed by Gustavus Rose, from 4-59 to 7*69 

 of fluoride of calcium were detected ; and they call the attention 

 of chemists to the association of the elements of Fluorine and 

 Phosphorus which takes place in the Phosphorite of Estremadura, 

 as it does in recent and fossil bones and teeth. 



The only practicable route at present for conveying this mineral 

 to the coast is by a six-days' journey in bullock cars, or on the 

 backs of mules, to Seville. 



3. Notes on the Cretaceous Strata of New Jersey, and other 

 Parts of the United States bordering the Atlantic. By C. 

 Lyell, Esq., M.A., F.R.S. 



The cretaceous and tertiary deposits of America, which inter- 

 vene between the Alleghany mountains and the Atlantic, bear a 

 great resemblance in mineral character to the sandy and argil- 

 laceous portion of the formations of the same age in the south-east 

 of England. If all the white chalk, with its flints, together with 

 the cherty beds of the green sand, were omitted, the remaining 

 cretaceous strata in our island would consist of loose incoherent 

 sand with green particles, red and highly ferruginous sandstones, 

 white sands, and (in some places) beds of lignite ; the overlying 

 tertiary deposits, consisting of marls, clays, and variously coloured 

 sands occasionally exhibiting green particles, like those of the 

 green sand below the chalk ; and as in the bottom of the London 

 basin near Reading. Such, for the most part, is the succession of 

 the beds in New Jersey ; and, further south, in Maryland and Vir- 

 ginia, the Eocene strata are often as full of green particles as the 

 cretaceous, so that they are only distinguishable by their fossils and 

 relative position. Even the Miocene strata are sometimes, as in 

 Virginia, of a blueish-green colour, and contain green particles of 

 a similar kind. This fact alone of the identity in lithological cha- 

 racter of the secondary and tertiary strata of the United States is 

 calcvilated to put us on our guard against inferring that the green 

 and ferruginous sands of New Jersey correspond in age to the 

 lower rather than the upper part of the European cretaceous 



