The state herald., 1916-10-01
02SZzG22A0G71S 0GLkAICT

the slime pores and canals are greatly developed
and must exude large quantities Of slime? Then
too. on deep-sea expeditions. favorable occa
sions. as for instance. a dark calm night, fishes
that have been brought to the surface and placed
in water were seen to Fash light from the ends
OF the tentacles or the phosphorescent pores
precisely as we should have expected from
study of these organs. Major Alcock in his
interesting volume. "A Naturalist In Indian
Seas" mentions a specimen brought up from
profound depth which "glimmered like . ghost
It lay dead At the bottom Of the pail OF tur
bid seawater" 40 that by Inference ss we'll
by actual observation, We must believe that what
We call luminous organs In deep-sea fishes. emit
light into the darkness about them. In the case
Of fishes totally blind. the absence Of light IL
compensated for BY the development Of enor-
nous antennaelike feelers. modified from IN
rays. that these fishes can feel their way.
ss II were, through the darkness.
The absence OF light. however. entails another
important consequence. As Is well known. no
plant life can exist in darkness. There is there
fore no vegetation Of any kind In the profound
depths Of the soa. The deepsea nshes are. In
consequence. all carnivorous the more powerful
ones seizing and devouring the weaker ones. II
Ia cold black world where might reigns
preme. Many have enormous mouths. and for.
midable teeth to insure holding the prey In
some forms the teeth 80 large that the mouth
cannot he shut!
The temperature Of the water In the profound
depths Of the sea. Ia always low and near the
freezing point. This ID true everywhere. even
at the equator. Undoubtedly this has an effect
upon the nshss. although II Is not yet known
what II 10. The amount Of oxygen dissolved In
the water also. In much less than In water nearer
the surface The breathing apparatus OF the
deepses fishes IL modified to suit their peculiar
conditions The gill nlaments have become much
reduced In size. and In q number Of Instances
some Of the gill arches bear sill hlaments At
all. The nshes are apparently adapted to .
much smaller oxygen supply than those living
in rivers or In the shallow sea.
When we think Of the vast diversity among
these fishes. tho question arises: Are they all
representatives Of a single family group that
has become specially adapted to life In the deep
sea: or dc they belong to different families or
groups! One need hardly be an ichthyoioxist
TO answer this question. Even curSory exam.
nation Of the plates In work on deepsea
fishes will show that different types are repre-.
sentcd. In fact. great many families In.
cludod In the deepsea fnuna. There are sharks
and rays salmonoids. herrings. perchcs. eels.
and representatives Of many other families. We
can explain this hcterogcncity among them IN
this way. We may imngine that fishes Of many
different kinds In their search. 10 TO speak, for
tho unoccupied corners Of the sea. found q haven
in these deeper waters wherc they were free
from pursuit by their enemies In the course Of
time they migrated farther and farther into the
deep. change In habits taking place part paasu
with the changes In structure. Having started
out with different organizations, and possessing
different degrees Of variability. they became dif.
fcrcntintcd In diverse directions. 10 that while
some developed enormous mouths powerful
teeth. or phosphorascent organs others became
bottor'iivins ana partly or completely lost their
eyes stu others developed long feeicrs for
cropping their way through the darkness Now
and again. however. Hshcs Of separate groups
developed similar structures 80 that there arc
many striking cases among dccp.sen fishes OF
what the biologist calls "convcrgcncc." or pnrai.
lclsm.
Tho museum has recently prepared 10, cxhi.
btion n number Of typical dccpSca fishes nr.
ranged IN the form Of q group The preparation
OF this exhibit involved many technical difficui.
ties. such ns tho modelling OF the fishes In trims.
parent or translucent media. to represent them
m gImmorng or shining With iitup "porthoics." "
Considerable experimenting was necessary To