orms of life. As species are produced and
exterminated by slowly acting and still existing causes, and not
by miraculous acts of creation and by catastrophes; and as the most
important of all causes of organic change is one which is almost
independent of altered and perhaps suddenly altered physical conditions,
namely, the mutual relation of organism to organism,--the improvement of
one being entailing the improvement or the extermination of others; it
follows, that the amount of organic change in the fossils of consecutive
formations probably serves as a fair measure of the lapse of actual
time. A number of species, however, keeping in a body might remain for a
long period unchanged, whilst within this same period, several of these
species, by migrating into new countries and coming into competition
with foreign associates, might become modified; so that we must not
overrate the accuracy of organic change as a measure of time. During
early periods of the earth's history, when the forms of life were
probably fewer and simpler, the rate of change was probably slower; and
at the first dawn of life, when very few forms of the simplest structure
existed, the rate of change may have been slow in an extreme degree. The
whole history of the world, as at present known, although of a length
quite incomprehensible by us, will hereafter be recognised as a mere
fragment of time, compared with the ages which have elapsed since
the first creature, the progenitor of innumerable extinct and living
descendants, was created.

In the distant future I see open fields for far more important
researches. Psychology will be based on a new foundation, that of the
necessary acquirement of each mental power and capacity by gradation.
Light will be thrown on the origin of man and his history.

Authors of the highest eminence seem to be fully satisfied with the view
that each species has been independently created. To my mind it accords
better with what we know of the laws impressed on matter by the Creator,
that the production and extinction of the past and present inhabitants
of the world should have been due to secondary causes, like those
determining the birth and death of the individual. When I view all
beings not as special creations, but as the lineal descendants of some
few beings which lived long before the first bed of the Silurian system
was deposited, they seem to me to become ennobled. Judging from the
past, we may safely infer that n