1887.] 351 [Marcou. 



in calling all the lower rocks of the palaeozoic and base of the 

 great series of strata, the Taconic System, referring them to a system 

 and not to a subdivision of a system as Sedgwick wrongly did. 



Murchison in claiming the rocks of the Second fauna — and 

 even the greatest part of the Primordial fauna — as belonging to 

 the Silurian, has committed precisely the same scientific error as 

 Sedgwick, putting two systems into one. Palaeontology has put 

 an end to the discussion and to the tendency of both Sedgwick 

 and Murchison to monopolize two systems. It has found a solu- 

 tion creditable to the two adversaries, and at the same time to 

 a third observer, Emmons, who without claiming anything, has 

 found the Primordial fauna, the very base and first step of Pal- 

 aeontology itself. 



Ordovician is absolutely valueless and creates a confusion with- 

 out any compensation. Its author has put it forward on the triv- 

 ial objection that the two opponents — Sedgwick and Murchison — 

 being both wrong, a new name was desirable ; and Professor Lap- 

 worth chooses a Welsh name, without consideration of the claims 

 either of foreign geologists or foreign geology. Priority was set 

 aside, and without any regard to the name of Champlain group 

 used in America since 1844 — a fact which he seems to ignore — he 

 has not hesitated in offering as a solution of the difficulty, a new 

 name whose only merit is in being British. American geologists 

 know well what is meant by Champlain group or Trenton fauna, 

 and to replace it now by Ordovician, when we try to give credit 

 and approve the claims of the distinguished authors and pioneers 

 of the discoveries made in the Lower Palaeozoic rocks of the 

 world, cannot be allowed. There is confusion enough without it. 

 Let us be content with the names offered in 1835 and 1844 by 

 Sedgwick, Murchison and Emmons. 



In fact, to Sedgwick we owe the Cambrian, limited to one fauna, 

 proved by Barrande to be the Second fauna; to Murchison we 

 owe the Silurian, limited to the Third fauna; and to Emmons 

 we owe the Taconic comprising the Primordial fauna. 



American geologists have the right of priority in the Taconic 

 system, and also they have priority in the name of Champlain 

 over Ordovician offered lately by the English. 



