The San Francisco call., 1903-12-13
Continued From Page s5. Column 1.

water and they do not shrink with the reverse
change Of conditions. One might be inclined
by an absolutely impermeable membrane.
HEART ACTION CEASES.
This would be an error, since. in the first
place. oxygen and carbonic acid pass. in a
state OF solution. through the membranes Of
me me animals or OF their eggs, and since more
brsnes Of the animals in both directions. A
relatively small increase of the concentration
OF potassium salts of the water for ex-
exple. causes the heart in eTnb-yos TO cease 10
beat and If the egg be brought enough
again begins to beat. 1t might be thought
from this that the animal is permea able for
question remains unanswered as to why the
animal does not become impoverished in salts
in distilled water and so die
/ believe that we must acknowledge that be-
sides differences OF osmotic pressure there
must be taken into account other conditions
for the exchange of fluids in animals like
fundulus. The secretion OF the kidneys and
the absorption of fluid in the intestincs show
mat tor the explanation Of the movements of
motto pressure alone not sufficient For
ANIMALS animals Ike Fundulus solution Of Mg iso-
Gus than distilled water
The second group includes those animals
rounded by semi -permeable wall which is
easily permesble for water, but impermeable or
tess pefmeahe for all many salts. The red
Diood corpuscles represent this type
AS IO The SEA CHCHIN.
The eggs OF the sea urchin also behave to
paced in distilled water they swell up and
snrink sInk again If they returned from the
Histiied water to the sea water. In these
forms forms distilled water has a mechanical action.
arls L,neehanical action may in itself inhibit
be placed in very dilute sea water the pro-
ceSSes Of cell division cease
a., Ihese processes. however. go on again II
me, me eggs are returned soon enough to the
d,, sIal sea water; In distilled water a muscle
ssss eHeads up 80 that its power of contraction
eases while this power returns IL the muscle
De removed from the water quickly enough
since this mechanical swelling does not take
pisce IN isotonic sugar eolutions in the ca Sc
Of the animals and tissues OF this group a
uIIutlon tIio OF the sea water serum with iso-
.Cnle sugar solutions is more harmless than a
dhution with distilled water
an lsotonic sugar solution is. however also
bolSSonoas ISSs Tor these animals is proved by my
iater investigation. This toxicity depends ar
sss- iesst IN part on the fact that salts or ions
surrounding medium. / suspect fhaf With ,ee rae
gara to the permeability Of semfpermeabIe
ehces exist in the different representstivas =,
.ni .nis ,gI9up. The living muscle is certainly
AIM i.eS .S easily permeable to potassium so
the influence or these salts on rbvfbmi son on
fractions show satisfactorily
EXAMPLE OF THIRD GROIrP
,,Ahis. as an example Of the third eroup We NAV
consider Gammarus. For this sninoppi s,1aa ay
solutlon isotOnlc with sea vatar ia o. ,9s susai
S"isv a. distilled water. In this case the tox
dieSystnr Dosh y. neola depends apparently on the
VI 19ioh OF salts or ions from the tissues
FROM his Investigations DIR Toab
draws the following conclusions:
ta) For the kind Of Gamnar,,s ,,.sa =, a..
thperiments distilled water and stoar soI,s
,o. "I,ch @ is isosmotic with sea water are al
.Sse SIquaiiS poisonous. In both solutions the
: iil.als I ole az room temperature in ahout bois
s,,,, 49, aouI' a hypotonic sugar solutions are m,
! ! "a i.eS-p So posisohous as sugar solutions which
e. however, small Inc dlHerencs
'o' II sea water is diluted by the addition