LOWER PALEOZOIC, 197 
clature your reporter has been guided by the foregoing consid- 
erations. 
Mr, C. D. Walcott, whose recent work in tlie stratigraphy and 
paleontology of the Taconic makes his opinion of great signifi- 
cance and value, and whom several geologists are disposed to 
follow entirely in their own opinion and recommendations, ad- 
vises the qualified adoption of the term Taconic in the nomen- 
clature of the Lower Paleozoic rocks.* It became necessary not 
only to adopt his discoveries and recommendations, coincident as 
they are with Mr. Ford's which preceded, but, owing to the re- 
cognition of the first mentioned principle already formally adopted 
by this committee (a dual nomenclature), to give them a somewhat 
wider application. In making this wider application, and in the 
multiplying of terms by the differentiation of paleontologic fi'om 
physical characters in accordance with the recommendation of the 
director of the United States Geological Survey, Major J. W. 
Powell, one of the great difficulties of geologists in choosing 
terms for the Lower Paleozoic is obviated. The various con- 
flicting terms are allowed to overlap each other without confu- 
sion by placing their conflicting elements in diiferent columns. 
It so happens that the chief conflict, that between the terms Cam- 
brian and Taconic, can be wholly obvitited by this differentia- 
tion. The Cambrian paleontologieally embraced only the second 
fauna, but physically it covered also the rocks of the first fauna. 
The Taconic pertained only to the first fauna paleontologieally, but 
physically it embraced also the rocks of the secoixl fauna. When 
separated thus they do not conflict, for the faunal idea is sepa- 
rated from the physical, and in its own ground, where it should 
be recognized, each has supremacy. 
Your reporter regrets exceedingly that, since the withdrawal 
by Mr. Walcott of liis former communication, read to the Com- 
mittee at the Spring Lake meeting, he has not received from him 
any other statement, and has to rely on the late published account 
of his latest discoveries, in the American Journal of Science. The 
facts there put forth, however, only confirm Mr. Walcott's former 
statements, and are consistent with the recommendations of this 
report. 
Other communications which have been sent to your reporter 
* See Note on p. 215 for Mr. Walcott's revised opinion. 
