ON NATURAL HISTORY MUSEUMS. 247
indeed, to exhibit merely a few types of the larger groups and sub-
groups. But the selection of an average representative of a group as
a type may lead to too high a notion of the sharpness of division be-
tween the several groups ; may lead, in fact, to the false impression
that nature is sharply cut into sections as is suggested by our classi-
fication, which by necessity is in large measure artificial. It must be
remembered that in nature we often pass, by the most gradual tran-
sition, from one group of organic forms to another; and it becomes,
therefore, highly instructive to exhibit in a collection such transitional
forms as will help to give a philosophical view of nature, without
attracting too much attention to our confessedly arbitrary landmarks.
Hence, in addition to an average specimen from each group there
should be exhibited judiciously selected aberrant forms—forms
which would serve to mark a passage from one group to another ;
that is to say, each group should be represented by the most typical
and by the least typical example which can be found; by a specimen
taken from the centre, and a specimen or two from near the circum-
ference of the group, where it is conterminous with another, or even
overlaps it. Thus, the great group of Carnivora might be repre-
sented, not only by a dog and a cat, and if possible by a bear, as
central types, but also by a seal, which would be taken as it were
from one of the margins of the group where it abuts upon the
whales.
But whilst a collection such as that here sketched out might
satisfy the requirements of the scientific student, it would be well to
appeal to our practical instincts by illustrating the uses of animals to
man in the shape of a collection of Economic Zoology; that is to say, a
collection showing the application of animal products to industrial
purposes, similar to the well-known series of the Department of
Science and Art at Bethnal Green. As an example of the importance
of these animal products, one might refer to the information which
would be given to the public by exhibiting a series illustrating the
manufacture of textile fabrics from raw materials derived from animal
sources, such as woollen and silken goods.
In that section of our natural history museum which deals with
the vegetable kingdom, this technological division would be much
more important than the corresponding part of the animal series.
So large a proportion of the objects with which we daily come in
contact are derived from vegetable sources, that a department of
Economic Botany can hardly fail to attract even those who have no