200 PROCEEDINGS OF THE CALIFORNIA 



Professor Marsh, of Yale College, was introduced. He had been 

 traveling since June with a large party, for the main purpose of 

 collecting and investigating the vertebrate fossils of the Rocky 

 Mountain re^-ion. 



In the upper cretaceous formations of Kansas, his party had 

 made probably one of the finest collections in the world. One in- 

 teresting discovery was the fact that the Mosasaurus, or its allies, 

 were in possession of hind legs — a fact not hitherto acknowledged. 



Many minute vertebrates, from the tertiary formation of Wyoming, 

 have been gathered. The investigations will furnish a theory for 

 clearing up cpiite a number of the geological puzzles, especially the 

 relations of the ancient fresh water lake basins east and west of the 

 Rocky Mountains. The discovery of a distinct 3Iiocene fauna in 

 Wyoming was an interesting result of their investigations ; also, 

 that the Pliocene basin, in Oregon, contains a large number of fos- 

 sil horses, and two or three of rhinoceros. 



Professor 'Whitney exhibited some fossils sent by Mr. J. E. Clayton to Pro- 

 fessor Joseph LeConte, and by the latter handed over to liim for examination- 

 They consist of a number of fragments of trilobites and brachiopods, which show 

 conclusively that the strata in wiiich they are embedded are of the age of the 

 Potsdam sandstone, or the lowest member of the Lower Silurian — the so-called 

 primordial rock of Barrande. The locality in which these fossils were discov- 

 ered is near iMireka, Nevada, about 100 miles south of Elko, on the Central 

 Pacific Railroad. The discovery is an interesting one, as the primordial fauna 

 had not been previously found west of the Big Horn Mountains, longitude 106 

 deg. Among the forms recognized are : Agraulos Oweni, M. and II.,or a spe- 

 cies closely resembling this ; Lhigu/cpis prima, Obohila, Conocoryp/ic, Paradox- 

 ides, &c. — all very characteristic of the primordial rocks. 



Dr. Blake read a paper on the composition of some of the waters 

 of the geysers, the remarkable feature of which was the enormous 

 amount of ammoniacal salts they contained. 



The following paper was presented in behalf of Mr. Garritt : 



