they find almost identically the same bones, having the same relations;
that they can name the muscles of the dog by the names of the muscles
of the man, and the nerves of the dog by those of the nerves of the
man, and that, such structures and organs of sense as we find in the
man such also we find in the dog; they analyse the brain and spinal
cord and they find that the nomenclature which fits, the one answers
for the other. They carry their microscopic inquiries in the case of
the dog as far as they can, and they find that his body is resolvable
into the same elements as those of the man. Moreover, they trace back
the dog's and the man's development, and they find that, at a certain
stage of their existence, the two creatures are not distinguishable the
one from the other; they find that the dog and his kind have a certain
distribution over the surface of the world, comparable in its way to
the distribution of the human species. What is true of the dog they
tell us is true of all the higher animals; and they assert that they
can lay down a common plan for the whole of these creatures, and regard
the man and the dog, the horse and the ox as minor modifications of one
great fundamental unity. Moreover, the investigations of the last
three-quarters of a century have proved, they tell us, that similar
inquiries, carried out through all the different kinds of animals which
are met with in nature, will lead us, not in one straight series, but
by many roads, step by step, gradation by gradation, from man, at the
summit, to specks of animated jelly at the bottom of the series. So
that the idea of Leibnitz, and of Bonnet, that animals form a great
scale of being, in which there are a series of gradations from the most
complicated form to the lowest and simplest; that idea, though not
exactly in the form in which it was propounded by those philosophers,
turns out to be substantially correct. More than this, when biologists
pursue their investigations into the vegetable world, they find that
they can, in the same way, follow out the structure of the plant, from