the scholar takes a good deal on trust from a
teacher, who, knowing the facts by his own knowledge, can describe them
with so much vividness as to enable his audience to form competent
ideas concerning them. The system which I repudiate is that which allows
teachers who have not come into direct contact with the leading facts
of a science to pass their second-hand information on. The scientific
virus, like vaccine lymph, if passed through too long a succession of
organisms, will lose all its effect in protecting the young against the
intellectual epidemics to which they are exposed.)

End of On the Study of Zoology.

GEOLOGICAL CONTEMPORANEITY AND PERSISTENT TYPES OF LIFE.*

([Footnote] *The Anniversary Address to the Geological Society for
1862.)

Merchants occasionally go through a wholesome, though troublesome and
not always satisfactory, process which they term "taking stock." After
all the excitement of speculation, the pleasure of gain, and the pain of
loss, the trader makes up his mind to face facts and to learn the exact
quantity and quality of his solid and reliable possessions.

The man of science does well sometimes to imitate this procedure; and,
forgetting for the time the importance of his own small winnings, to
re-examine the common stock in trade, so that he may make sure how far
the stock of bullion in the cellar--on the faith of whose existence so
much paper has been circulating--is really the solid gold of truth.

The Anniversary Meeting of the Geological Society seems to be an
occasion well suited for an undertaking of this kind--for an inquiry,
in fact, into the nature and value of the present results of
paleontological investigation; and the more so, as all those who have
paid close attention to the late multitudinous discussions in which
paleontology is implicated, must have felt the urgent necessity of some
such scrutiny.

First in order, as the most definite and unquestionable of all the
results of paleontology, must be mentioned the immense extension and
impulse given to botany, zoology, and comparative anatomy, by the
investigation of fossil remains. Indeed, the mass of biological facts
has been so greatly increased, and the range of biological speculation
has been so vastly widened, by the researches of the geologist and
paleontologist, that it is to be feared there are naturalists in
existence who look upon geology as Brindley regarded rivers. "Rivers,"
said the great engi