Correspondence . 257 
shows the unconformity between the Cambrian and Etcheminian, 
which might exist without being traceable in limited exposures of con- 
tact. 
Mr. Walcott cites the case of an intrusion of sandstone into the 
Trenton terrane as a parallel case to the white sandstone at the base 
of the St. John group; it is, however, not a parallel; in the former case 
the sedimentation and fauna are the same, above and below the sand- 
stone, in the latter they are not. This difference in sedimentation and 
fauna is apparent everywhere in Canada at the contact of the Etche- 
minian and Cambrian. 
Mr. Walcott does not seem to be much more happy in his ap- 
plication of new names to the Cambrian, etc., of the Canadian Atlantic 
provinces, than in his search for the Olenellus fauna. 
He has resurrected from a quiet corner of his "Correlation Papers," 
p. 360, a name (in brackets) that in i8gi he applied to a geological 
section he had not seen; his right to apply it seems dubious, as he did 
no work there; and the utility of adding another set of local names to 
those of the St. John group, seems still more questionable. The 
"Seely quartzite" is not on Seely street and the section he refers to is 
on another street; the "Ratcliff" section shows only a part of the 
"shales," the fossils are distorted, and only one subfauna of Para- 
doxides has been obtained there; other sections show as many as 
three subfaunas. The whole of the St. John terrane has been worked 
out by the Canadian survej^ors, its faunas placed, and its sedimenta- 
tion described. 
Mr. Walcott uses the name Algonkian for all the terranes between 
the Cambrian and Archaean. An exactly similar application was 
previously made by the late Sir Wm. Dawson of the name "Eozoic;" 
surely a much happier choice as an equivalent of Palaeozoic, Meso- 
zoic, etc. Mr. Walcott's remarks on the rocks below the Cambrian 
and Etcheminian would have had a more definite value if he had used 
the local names applied by the members of the Canadian geological 
survey, in place of Algonkian. 
In conclusion I may say that though Mr. Walcott seems disposed 
to brush aside the names and results obtained by the Canadian geolo- 
gists in this region, he has not done the work which will warrant this 
proceeding. A useful work within his own province would be to un- 
ravel the tangled Cambrian faunas of Washington Co., New York, or 
ascertain what faunas occur in the 1,000 feet of measures, between the 
base of the Palaeozoic and the original Olenellus fauna of western Ver- 
mont. 
G. F. Matthew. 
P. S. — I have not thought to refer, except in very general terms, 
to the difficulty which Mr. Walcott's view of the continuity of the 
Eopaheozoic sedimentation introduces into the succession of the Cam- 
brian faunas — In Newfoundland Mr. Walcott finds the Protolenus and 
Paradoxides faunas follow in regular sticccssion to the Fauna of Olen- 
ellus [Holmia] brirggeri. Where is the fauna of Olenellus thompsoni? 
