Rutland weekly herald. [volume] (Rutland, Vt.) 1859-1877, 1876-09-28
Huxley on Evolution.
TIE HORSE AS A TYPICAL INSTANCE o.
EVOLUTION.

TIE HORSE AS A TYPICAL INSTANCE OF
EVOLUTION.
Professor Huxley's couyge of three
lectures on "The Direct Evidence OF
Evolution" which he ended at CHECKER
ing hall Monday evening, has through
out been listened to with the atten-
ton which intelligent audiences are &C
customed to give TO the exposition of al
important doctrine by profound man,
who is known to be the most intimately
versed in it, and who speaks either as
| its supporter or its opponent. Evident
| ly his audience has been IN sympathy
| with him to singular Edegree, and, as
| he has always spoken with gravity,
though at times with some slight marks
| of irritation at futile criticism which
/ seems to be,unneeessarily irksome to him,
| has INDUCED in no flights of eloquence
/ such as popular lecturers on scientific
| subjects a re wont to display to the gap
| ing multitude, its intellectual level may
/ fairly be taken as above the average.
| Last evening he. began his lecture with q
| brief resume of the grounds trayersed
| in the two that had preceded it. 1t had
been shown that the evidence of fossil
/ remains is consistent with and favorable
to the doctrine of evolution, though not
demonstrative of it; that as we go back
| in time we find the great intervals that
now exist between the larger groups of
| animals more or less obfiterated by the
| discovery of intermediate forms, such
as those which close the gap between
! birds and reptiles, SO that 1t is hard. TO
say where one leaves off and the other
commences and that this evidence Is as
weighty as that which leads men to af-
firm anything as true in ordinary mat
tiers, But it is not absolute demoBstrar
ton, because these intermediate forms
do not occur in the exact order in which
they should be found to show that they
are really intermediates between. birds
and reptiles. They exist in conteInpo-
| Fane0us deposits, but they Should be in
regular line of progression: if it is to be
shown that the steps are graduated from
| the lower to the last form. There
would be the highest demonstraiiye evi-
deuce if in some older formation reptiles
were found, birds in some newer, and
intermediate beings between them. The
proof of evolution cadnot be looked
upon as complete till such evidence
is forthcoming. OF late years
such evidence has been found, in an
amount surprising when we remember
that to get at it we must find undistufbed
deposits and fossils perfect or not much
injured. Every division of the animal
kingdom has in late times furnished such
evidence, and from the mass one animal
may be selected, which shall be the
hpree-tssEgs, inctudiug the ass, zebra
ard k1ldred fefrna. The horse, too,
preseAts one Of the most perfect exam
Piles of machinery IN the anitnal king
dom, being perfectly adapted TO il. pur-
pose and doing a surprising aniouns Of
work with the least fuel. The haisrea
of its parts, the rhythm of their action,
the slender and elastic legs with their
powerful muscles, its feeding and di-
gestive apparatus are all of the highest
order. All this depends upon its struc-
ture, TO understand which an exsmina-
ton of its anatomy is necessary. The
upper bone of its fore leg is analogous
to the humerus in man, the next to the
forearm with its radius and ulna; the
knee to the wrist; the coronet bone to
the middle finger, and the hoof to the
nails. There seems, indeed, on first
view, to be but one bone in this fore
arm; but two can be traced for some
distance, though not completely down -
the nina being fused with the radius
4 careful examination shows that the
ulna is not wanting, aud in the young
colt il is sornetiHaes Piainly seen, uut as
age advances it uniteS with the radius
aud there are also rudimeniary meta
carpal bones for the socCn3 and fourth
fingers. Sometimes monsters are found
with the toes cooap'ete. In the hind leg
the shin hone seems bat 3 splint. repre-
- T}s,la Of
end clearly marks il rs such where it is
united with tue tiOia The medium toe
IS like ours, two splint bones being Tudl-
Inentary second and fourth toes, with
the metatarsal bones joining, The
stomach ard digestive apparatus ars
highly differentiated; there should
strictly be forty four teeth, but there
are rarely more than foTty, and the mare
commonly has but thirty ak, the
"tushcs! fIeyIfg seldom developed There
are six inciscrs above and six below,
from which the age Of comparatively
young horses may be told by the pres
eBce of 3 dark patch. The young foai
has deep pit in each incisor, into which
the fodder gets and .carhoDizss, but with
age the teeth are worn down until this
patch disappears. The grinders work
upon each other like mill stones, and
keep the form of their surfaces, SO that
they long remain intact. If evolution
be true, what should we expect to find
in the history Of the horse 2 We know
that typical naInai5 are claracterigsd
by distinct radius aud ulua; gGDer
ally five TOES, often nut quail, bat
as fingers wen developed. Ia the leg
T are complete movable h0ula ami iibia,
and on the hind f0H five dittinct toes
hence If q differentiated animal like the
horse has developed from simple main
malian form, We should find IL The
rocks, if il be there, traces of graduated
forums back to,one with q radius and
ulna fibula and tibia, and five tees gu
the hind and fore feet. The teeth
should also be those of the Typical mann
mai In the ploc"ue formation of the
upper tertiary dep, tsit, many remains. OF
horses IRE found IL Europe, and many
| in the post teri iffy, but they differ III
no essential pcint from the horse OF the
present. Tue same is true of the later
pliocene, but in the middle and earlier
I plioCene horses are Hound whose general
osteoiogy is like that of our own horse,
but in the bones of the fore and bind
legs are two splints, that must have
b6t Ii ltttH- LlEAc my IitzNS
acts This animal is the hipparion,
three toes. being developed fully in mum.
her bat not in. size The ulna can be
/ traced about as in the horse, whose ina
mediate predecessor was the hipparion.
In Central Germany, France and Greece
remains are found of an animal which was.
broadly like our horse, but the teeth and
limbs differed. This is the anchither-
Jun, with three complete toes, the mid
die proportionately small, and the later
al ones resting on the ground as func.
tional toes. In the fore arm the. radius
and ulna are Gistinguishable throughout
their whole length; the. hind foot has
three toes, and the ffbnla is sometimes.
complete and separate throughout its
whole length. The teeth have only
rndimentary pit, and the canine in both
sexes the grinders are generally com
plete, the crows are. short and contain
no cement such as exist IN our horses
they are the simplifed teeth of the
horse. This was all we knew of the
ancestor of the horse but few years
ago. Every one. of these forms have
been modified in species, and we cannot
be sure from which species equus was
6ariuaA h,Jt r ,staI b..ra