The herald and mail. [volume] (Columbia, Tenn.) 1873-188?, 1874-01-23
Agassiz on Darwinism.

/
Prof. Agassiz has long been known AZ
an unbeliever in Darwinism, and the un'
compromising enunciatioD of his views,
which is to appear in the January Allan.
tic, although it defines his position more
clearly, will surprise no student of his
works. In this essay, Professor Agassiz
gave synopsis of his reasons for not
holdiog the Darwinian doctrines, pre-
paratoTy to a more detailed statement
which he intended to make in future
numbers of the magazine. This sketch
! the great naturalist will never complete,
and to its value is added the melancholy
interest of being the last finished work
from the hand to which the students
and lovers of natural science owe so
much.
1t begins by saying that "The law of
evolution, so far as its workings is un
derstood, is a law controlling develop
ment and keeping types within appoint
ed cycles of growth, which revolve for
ever upon Themselves, returning at ap-
pointed intervals to the same starting
point, and repeating through a success
sion of phases the same course. These
cycles have never been known to oscil-
late or to pass into each other indeed,
the only structural difference known be-
tween individuals of the same stock are
monstrosities, or peculiarities pertain
ing to sex, and the latter are as abiding
and permanent as type itself" His
next assertion is that no primary divis-
ions of the animal kingdom will stand
which will not bear the test applied b7
Cuvier to his four great groups, Radi-
ate, Mollusks, Articulates and Verte-
brates that is to say, the test of dis
tinct plan of structure for each.
The article then briefly reviews the
different books published by Darwin,
and says that Pangenesis" in which
the whole theory is summarized, "does
but prove more conclusively what was
already known-namely, that all do
mesticated animals and cultivated plants
are traceable to a distinct species, aud
that the domesticated pigeons which
furnish so large portion of the Illus
tration are, notwithstanding their great
diversity under special treatment, no
exception to this rule" The review
closes with the assertion that the great
er part of the argument, both with OAR
win and his followers, is purely mega
tive, and rests partly upon the assump-
tion that, Gin the succession of ages,
Just those transition types have drop
ped out from the geological record
which would have proved the Darwin
ian conclusions, had these types have
been preserved, and that, in the living
animal. the process of transition is too
snbtIe for detection, thus throwing off
the responsibility of proof with respect
to embryonic growth and geological
succession"
Concerning the famous discovery"
made by Kowalevsky, of the presence
in the Ascidiaus of a string of cells
corresponding to the dorsal cord in Yer
tebrates, the article saws that the exis-
tence of this string of cells was previ-
ously known to naturalists, and that
he himself had intended to say some
thing of their nature and position had he
not been anticipated by Won Baer, who
has recently published pamphlet up
on the development of the Ascidlans as
compared with the Vertebrates, in
which pamphlet he shows that the
string of cells runs along the ventra
side of the body of the Ascidians, and
that their development has no true
homology with that of the VeItebrates.
"To say that the .st Vertebrates or
In6lT UIORGulbOib CdIElNu blASlA baNh~
bones in this manner, said Professor
Agassiz, "is about as reasonable as to
say that they walked on their h ads.
The doctrine of Heckel, that star
fishes are compound animals, made mp,
as it were, of worm-like beings, united
like rays in one organism, a doctrine
which, if true, would establish a tran
sition fl Radiates to Articulates, is
pronounced to be all assumption, with
out foundation in the structure of the
starfsh. The arms of these animals
being made up of the same parts as the
vertical zones of all Radiates, and ar
ranged around vertical axis, cannot be
compared to those of any Articulate, in
which class the parts are arranged along
a longitudinal ak s.
The topics of metamorrhosis, here
ditary and natural succession, are very
briefly considered, and the article closes
with a consideration of the geological
side of the question, in which ground
is taken against the theory of transmits
sion, since the whole history of geolog
ical succession shows that the lowest in
structure is by no means earliest IN
time, and since, therefore, it may be
said that great diversity of types has
existed from the beginning.