58 



Allanite. East Bradford, Chester Co. Pa. Rammelsberg, Ann. 

 Ch. u. Ph. Lxxx. p. 85 ; Kenngott, Uebersicht ]\Iin. Forsch. 1850- 

 1851, p. 131 ; Sharswood, Tr. Acad. Sci. St. Louis I. p. 685. (This 

 mineral has been classed as Orthite by Ptammelsberg. It has 

 been arranged nnder the variety Allanite, by Professor Dana, in 

 his Manual of Mineralogy.) 



Thuringerwald. 



Hitteroe. Scheerer. 



Werchoturie. Hermann. 



Gottliebsgang. Berzelius. 



Stockholm, Park at. Berlin. 



Kullberg, near Stockholm. Berlin. 



Eriksberg in Stockholm. Bahr. 



PyrortUte. Kararfvet near Fahlun. Berzelius, Afh. i. 



Fys. och. Kemi. v. 49. 



Ytterby. Berlin. 



Dr. C. T. Jackson exhibited a small trilobite from Braintree, which 

 proved to be the Paradoxides Harlani, and observed that this fossil 

 seems to be identical in Braintree and Newfoundland. The P. Ben- 

 netti from St. Mary's Bay, according to Barrande, is nearly related to 

 but not identical with the P. spinosus of Bohemia. 



Mr. Marcou remarked that Massachusetts and Newfoundland bore 

 about the same geographical relation to each other as Bohemia and 

 Scandinavia ; in both cases the trilobites of the primordial fauna being 

 nearly related but distinct species. Indeed, it is the opinion of Mr. 

 Barrande that there was a greater diversity in the ancient than in 

 the modern crustaceans of these regions. 



Professor Agassiz observed, as to the dilFerencc between ancient and 

 modern species, that there were representative species in all geological 

 periods, as well as at the present time. That there may be synchro- 

 nism of deposit without identity of fossils must be evident, if we 

 glance at the present distribution of animals ; if at the present epoch 

 the fauna of America and of Australia should become fossilized, 

 there would not be the slightest resemblance between the represen- 

 tative species of the two continents. The paleontologist must be 

 ready to admit that very different fossil faunae may be contemporane- 

 ous, and that their difference does not necessarily imply a distinct 

 zoological age. 



Mr. Marcou stated that Mr. Hitchcock's section in Vermont, exhib- 

 ited at the last meeting, was not made with reference to the idea that 

 the fossils were primordial, and therefore that we cannot draw from it 

 the conclusions Avhich only a section made with this special object in 

 view could justify. He drew a section of Bald Mountain, Washington 



