:- 
Pa ile aes eee ee Se en ee ee ge es See Ee age Se 
FE eG ee ee a eS on ene ee, ae a RL ees mare = 
J. P, Lesley on the Coal-measures of Cape Breton. 193 
Coal-measures may be distinguished; but within these aes 2s 
the differences are purely local, and afford no means for 
identification of beds in distant place 
o not desire to offer any ont on the questions raised 
by some American geologists, as to the extension of the term 
Carboniferous to the Chemung group; but I know as certain 
facts, that the flora of the — Coal- ao ae under the marine 
Ww 
Professor Hall and others, and also of the groups in - Pennsyl- 
vania named, by Rogers, ‘Vergent, and Ponent (? IX and X of 
Mr. Lesley), is as deci idedly Devonian, and quite distinct from 
= the Carboniferous period.” 
r. Lesley’s ability as a stratigraphical geologist, I have 
the besbein respect; and, with reference to the present subject, 
woul merely desire to point out that he may not have possessed 
a sufficient number of facts to warrant some of his generaliza- 
tions, on which in the meantime I would, for the reasons above 
stated, desire geologists to suspend their judgment. 
J. W. Dawson. 
McGill College, Montreal, February 18th, 1863.” 
Mr. Lesley remarked that he read this communication of his 
friend, Dr. J. W. Dawson, with great pleasure, as it wou 
and any undue bhp i being attached to his own 
than to defend those opinions ptotealion in his paper, which had 
drawn down so earnest and valu able a iro from so high a 
sat identity in organic forms continues to be accepted as 
the supreme test of stradigeaphieal horizon, discord is inevitable. 
When paleontology is prepared to return under the mild 
aoe 
_ minion of her mother, lithology, which she has at ledst one-half 
cn Nesp ciy geology will advance more rapidly in her wor 
r. Dawson’ 's first t objection is a begging of the very ques- 
se whether the Coal-measures of Nova Scotia are ‘‘ enormously 
_ dey 
That, in one spot of the earth’s surface like Nova 
on Devonian Flora of Eastern — Quar. Jour. Geol. Soc. 
Lin iva ering 1862, Also this Journal, May, 1863 
Am. Jour, Sc1t.—Szconp SuRres, Vou. XXXVI, No. 107.—Sepr., 1863, 
25 
