condition of the
surrounding universe.

There is not a fragment of the organism of this humble animal, whose
study would not lead us into regions of thought as large as those which
I have briefly opened up to you; but what I have been saying, I trust,
has not only enabled you to form a conception of the scope and purport
of zoology, but has given you an imperfect example of the manner in
which, in my opinion, that science, or indeed any physical science, may
be best taught. The great matter is, to make teaching real and
practical, by fixing the attention of the student on particular facts;
but at the same time it should be rendered broad and comprehensive, by
constant reference to the generalizations of which all particular facts
are illustrations. The lobster has served as a type of the whole animal
kingdom, and its anatomy and physiology have illustrated for us some of
the greatest truths of biology. The student who has once seen for
himself the facts which I have described, has had their relations
explained to him, and has clearly comprehended them, has, so far, a
knowledge of zoology, which is real and genuine, however limited it may
be, and which is worth more than all the mere reading knowledge of the
science he could ever acquire. His zoological information is, so far,
knowledge and not mere hearsay.

And if it were my business to fit you for the certificate in zoological
science granted by this department, I should pursue a course precisely
similar in principle to that which I have taken to-night. I should
select a fresh-water sponge, a fresh-water polype or a _Cyanaea_, a
fresh-water mussel, a lobster, a fowl, as types of the five primary
divisions of the animal kingdom. I should explain their structure very
fully, and show how each illustrated the great principles of zoology.
Having gone very carefully and fully over this ground, I should feel
that you had a safe foundation, and I should then take you in the same
way, but less minutely, over similarly selected illustrative types of
the classes; and then I should direct your attention to the special
forms enumerated under the head of types, in this syllabus, and to the
other facts there mentioned.

That would, speaking generally, be my plan. But I have undertaken to
explain to you the best mode of acquiring and communicating a knowledge
of zoology, and you may therefore fairly ask me for a more detailed and
precise account of the manner in which I should pro