The Seattle post-intelligencer. [volume] (Seattle, Wash. Terr. [Wash.]) 1888-1914, 1898-01-29
PosT-NTEILIGENCER SATURDAY.

X from the evolutsonist'e standpoint Ia its
locatiun. Instead OF lying on the dorsai
side OF the aianentary tract. as II does in
every vertebrate without exception IL re-
verses --ais position. It's long chain Of gang
ia. linked by 4 nerve card. runs along the
lower side OF the body, instead Of along
the back And, 10 make the matter worse.
az IT'S anterior end the cord divides. ard
passes as hop about the esophagus or
the worm. 10 terminate in a final ganglson,
which takes the place Of a brain. and Les
where the brain should. according 10 YER
febrase customs. on the upper side of the
body.
So VERY general is this arrangement OF
the. nervous system among the lnyer.e-
hrates and 50 universal the dorsal arrange
ssaenf among vertebrate<, that his das-
erepancy may be said 10 represent the
most important of those missing links
about which people are so fond OF taking.
II i a Ink very far removed in the chain
from where the popular conception places
It.
Notwithstanding this discrepancy. Prof
Mlnos along with a host of other natural
lists. Is disposed TO think tina, these worms
are the true ancestors OF the vertebrates-
The discrepancy in the nervous system Is
EXPLAINED by supposing that the terminal
upper gangiion became degeneratsd as the
animal evolved. its place being taken by
the one next it In the chain, winch lies. IKE
finally the animal body whole reversed
its position so that ultimately it became
customary for Il To move about with its
nervous side uppermost. For an aquatic
worm. wriggling about in more or less in
different attitudes. to make such change
does not seem very unreasonable.
There are those at the meeting. how
ever. who demur very strongly at this
view Of the case; in particular DIR. Gas.
kill. the famous London anatomst who
has theory of his own in the matter to
defend. This theory supposes that not the
worms. but the jointed creatures. such
as crabs. holsters and insects. are the
true ancestors We are searching for. These
creatures present the same difficulty re-
garding the nervous system that Is shown
by the worms but DIR. Gaski.l meets it in
a novel way. He believes that the fore
most ganglion. which does service for
brains in the insect. is the direct fore
runner of the brains OF all higher crea-
lures. He thinks that the rest of the
nervous system, from being In the first
place merely iooped about the esophagus.
came finally. as il developed. to surrond
the entire digestive tract. until that i'm
portant structure ceased TO be or any
use, remaining as mere rudimentary
cavity within the brain of the vertebrate
One hears sometimes in unscientific cir
Giles of d man having his brains In his
stomach, but, according to Dr. Gaskiil,
every one has the rudiment of stomach
in his brain. Meantime. of course. new
aIimentary tract was developed to take
the place of the old one whose domain
had been encroached upon by the growing
nervous system.
The evelutionist. however, is little guild
ed by mere external appearances, and he
finds no difficulty in bridging the gap be-
tween a worm-lke fish and a fish In ar
NOR For that matter he finds no great
stumbling block between the lowest hsh
and man himself-nothing at all to be
compared to the puzzle supplied by the
difference in nervous system above out
lined, which is the real barrier between
the true worm and the worm-like fish.
Some day the students of lower forms or
life will bridge this gap. through observa-
ton of the development of the embryos
of the creatures under discussion. Until
then We cannot be sure whether the num-
bic earth worm or the busy bee IS our
nearer kin. But ii is a helpful check upon
ones pride of lineage 10 reflect that one
or the other of these, or at any rate some
other creature equally humble. was our
undoubted ancestor.-Omaha Bee.