520 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 16, 



therefore, be considered, in the present state of our information, to be 

 the northern Umit of the extensive Tertiary formation along the shore 

 of the Pacific. The fossils enumerated by Dr. Grewingk include some 

 well-known species of the Tertiary age in Europe ; among which may 

 be mentioned Cardium Grcenlandicum, Chemn., C. multicostatumy 

 Venerupis Petitii^ Desh., Mi/a arenaria, Tellina edentida. Sow., 

 Astarte corrugata, Mytilus Middendorffi, and Ostrea longirostrisy 

 Lamk. Some new species of the same genera are added by Dr. 

 Grewingk, together with some forms of Saxicava, Pectunculus, Nu- 

 cula, Pecten, Crassatella, and Venus. 



Fossils of the Drift. — Organic remains of the Pleistocene or Drift 

 Period appear to be much more numerous on the west than on the 

 east side of the Rocky Mountains. The cliffs and sand-banks, 

 wherever they have been examined along the coast, abound with 

 recent shells of the genera Cardium^ Venus, Turbo^ Murex, Solen, 

 Trochus, Mytilus, Mya, and Tellina. Fossil remains of Mammalia, 

 especially those of the Mammoth, are likewise abundant. Teeth of 

 this animal have been discovered on the banks of several rivers north 

 of Mount St. Elias ; and there is a celebrated locality at Escholtz 

 Bay, in Kotzebue Sound, where the thawing and wasting of the frozen 

 cliffs is continually exposing the bones and tusks of Mammoths and 

 other quadrupeds. Dr. Buckland, in his interesting account of the 

 specimens collected at this place during Captain Beechey's Voyage, 

 enumerates fragments of bones of Mammoths and of the U7'us, the 

 leg-bone of a large Deer, and a cervical vertebra of some unknown 

 animal, different from any that now inhabit Arctic America. Along 

 with these were found also the skull of a Musk-ox and some bones of 

 the Rein-deer, in a more recent condition than the others. Similar 

 remains, including those of the Mammoth, have likewise been dis- 

 covered, according to Dr. Grewingk, at Cape Nugwuljinuk, at Bristol 

 Bay, and at Norton Sound, as well as in the Pribulon Islands, and 

 lastly at Unalaschka. 



The vast profusion of the bones and tusks of the Mammoth in 

 Siberia and the adjacent islands is well known, and it is a somewhat 

 remarkable circumstance that no similar remains have as yet been 

 detected in the corresponding latitudes of America to the east of the 

 Rocky Mountains. None have hitherto been found, according to Sir 

 John Richardson, in the Hudson's Bay Territories, though the annual 

 waste of the banks and the frequent land-slips would have revealed 

 them to the natives or fur-traders had they existed even in small 

 numbers. They are rare also, or altogether wanting, in Canada ; 

 but in the Valley of the Mississippi the " bone-licks " are well known 

 as most extensive, and as furnishing the remains of many new species 

 of quadrupeds. In whatever way the circumstance may be accounted 

 for, it seems to confirm the opinion to which most American geolo- 

 gists have arrived, that the countries on the eastern and western sides 

 of the Rocky Mountains have been elevated at different periods and 

 under different geological conditions. 



