126 
discovery only tends to link yet more closely the rocks of 
each successive period one with the other. 
And if, in placing the whole of the flowerless plants of 
the lower part of the series, I appear to sin against the 
obvious facts, that most of the Cryptogamic orders continue 
to the present day, I beg it will be understood, that by this 
arrangement I have only attempted to indicate a maximum 
for each succeeding epoch; and by no means would assert, 
that the higher tribes had not their roots further back in 
time than we have yet discovered them. And still less, of 
course, to assert, contrary to the fact, that branches of the 
Cryptogamie group do not persist till now,—the humble de- 
scendants of what was once the reigning dynasty. 
I do not think it necessary to quote Dana, whose pregnant 
comparison of successive geological epochs with human dy- 
nasties must be fresh in the memory of every geological 
student. The commencement of one ruling caste in the his- 
tory of men, as of lower organic groups, during the culmina- 
tion of another, is so natural and familiar to us, that it only 
needed the genius of that accomplished author to clothe it 
in appropriate language—and then to become an accepted 
axiom in natural history. 1 therefore make no apology for 
restricting the Cryptogamia to the Palozotc; or the Flowering 
plants to the NVeozote strata. And I wish the tabular scheme 
to speak for itself, with only the following remarks : 
1. We have, in the early stratified rocks, evidence of the 
existence of banks of seaweed and nullipore, only by means 
of the beds of Graphite and stratified limestone, which occur 
all over Canada. The origin of these is not doubtful to the 
chemist, and Mr Sterry Hunt has already claimed them as of 
Vegetable origin. 
2. In the Lower Cambrian rocks of Sedgwick, traces only 
of low Alge have been found (Corallines and other calcareous 
forms): and in the Silurian, fronds of seaweed, apparently as 
