174 PROCEEDINGS OP THE AMERICAN ACADEMY 



XI. 



THE "TA CONIC SYSTEM," AND ITS POSITION IN 

 STRATI GRAPHIC GEOLOGY. 



By Julks Marcou. 



Communicated December 10th. 1884. 

 CONTENTS. 



I. Introduction 174 



II. Historic : 1837-1881 .... ..175 



III. A"ertical anj General Section of tlie 



Taconic System. — Infra-Primordial, 

 Primordial, and Supra-Primordial 

 Faunae 221 



IV. The Taconic of Eureka (Nevada) and 



of the Grand Canon of the Colorado 



River (Arizona) 22!) 



V. Geographical Distribution of the Ta- 

 conic. — Norway 235 



VI. Taconic versus Cambrian and Silu- 

 rian 244 



Vll. Conclusion 255 



I. Introduction. 



De Verneuil has wittily said, that " iho iirimordial fiiuna of Bo- 

 hemia has made a fortune ; one might also say, that the Taconic 

 fauna in America has not made a fortune " ; although Barrande's con- 

 clusion on the matter is thus stated : " Simple and impartial witness of 

 the discussions «of American geologists, we recognize in the Taconic 

 fossils the same order of succession as that which is established in the 

 palaeozoic regions of Europe." * 



The publication of this memoir will not cause all opposition to the 

 " Taconic System " to cease. When we remember the favorite dogma 

 of mud-currents and gigantic waves of water in the transportation of 

 erratic boulders, and the lively and passionate opposition that was 

 made to the glacial theory of Agassiz and to the ice age, we see that 

 an opposition of forty years' standing is " hard to die." Though tlie 

 dogma of the transportation of boulders by water has been again and 

 again demolished for fifty years past, it every now and then reappears 

 dressed up anew, as a fresh contribution to geological progress. 



Two sorts of manifestations are made against the Taconic system 

 which escape refutation by their intangible nature. One is, simply to 



* See " Documents anciens et nouveaux sur la Faune priinnrdiale et le 

 Systeme Taconique en Amerique, " par J. Barrande, pp. 225, 228, and 293 

 (Pans, 1861). 



