on the Taconic System, 119 



by Mr. Barrande himself, when he presents to us, as a preliminary 

 work, a section across the centre of Bohemia. With all willing- 

 ness to accept Mr. Barrande's determination, fortified and sus- 

 tained as it is by the exhibition of his magnificent work npon the 

 trilobites of these strata, we had not yet the means of parallelizing 

 our own formations with those of Bohemia by the fauna there 

 known. The nearest approach to the type of primordial trilobites 

 was found in those of the Potsdam sandstone of the northwest, 

 described by Dr. D. D. Owen ; but none of these had been gene- 

 rically identified with Bohemian forms ;* and the prevailing 

 opinion, sanctioned as T have understood by Mr. Barrande, was 

 that the primordial fauna had not been discovered in this country, 

 until the re-discovery of the Paradoxides Harlani, at Braintree, 

 Mass. The fragmentary fossils published in vol. 1, Palaeontology 

 of New York, and similar forms of the so-called Taconic system, 

 were justly regarded as insuflBcient to warrant any conclusions. 

 It then became a question for palaeontologists to decide, whether 

 determinations founded on a physical section in a disturbed and 

 diflicult region of comparatively small extent, were to be regarded 

 as paramount to determinations founded on examinations, like 

 those of the Professors Rogers, extending over a distance in the 

 line of strike of five or six hundred miles ; and those of Sir William 

 Logan over nearly as great an extent from Vermont to Gaspe. 



It is not possible for me, at this moment, to give the time ne- 

 cessary for a full discussion of this important subject. In present- 

 ing these few facts in this form, I am far from doing it in the 

 spirit of cavilling, or as an expression of distrust in any direc- 

 tion. It is plain that the case is not met in Mr. Barrande's plan 

 of successive trilobitic faunae ; and the facts yet brought out do 

 not serve to clear up the difficulty. It is evident that there is 

 an important and perplexing question to be determined, — one that 

 demands all the wisdom and sagacity of the most earnest inquir- 

 ers, and one which calls for the application of all our knowledge 

 in stratigraphical geology and in palaeontology ; — one in which 

 cooperation, good will and forbearance are required from every 

 one, to harmonize the conflicting facts as they are now presented. 

 The occurrence of so many types of the second fauna in the 

 rocks at Point Levi, associated with a smaller number of estab- 



* The glabellae of small trilobites undistinguishable from Conocepha- 

 lus occur in the Potsdam sandstone near Trempaleau, Wisconsin, on 

 the Mississippi river. 



