The state herald., 1915-10-01

the slime pores and canals are greatly developed
and must exude large quantities OF slime? Then
too on deep-sea expeditions. favorable occa.
sons, as for instance. dark calm night. fishes
that have been brought to the surface and placed
In water were to fash light from the ends
OF the tentacles or the phosphorescent pores,
precisely as we should have expected from a
study OF these organs. Major Alcock. In his
interesting volume "A Naturalist In Indian
Seas mentions a specimen brought up from n
profound depth which "glimmered like ghost
as II lay dead ut the bottom OF the pail OF tur.
bid seawater So that by inference. as well as
by actual observation. must believe that what
we call luminous organs In deepsca fishes. emit
light into the darkness about them In the case
OF fishes totally blind the absence OF light is
compensated for by the development OF enor.
nous antennaelike feelers. modified from I'm
rays. so that these fishes can feel their way.
as 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 sea. The deep-sea fishes are. In
consequence. nll carnivorous. the more powerful
ones seizing and devouring the weaker ones II
Ia cold black world where might reigns All.
preme. Many have enormous mouths and for.
midable teeth to Insure holding the prey In
some forms the teeth are so large that the mouth
cannot be shut,
The temperature OF the water In the profound
depths OF the sea. IL always low and near the
freezing point. This Ia true everywhere. even
at the equator Undoubtedly this has an effect
upon the fishes, although II is not yet known
what II Is The amount OF oxygen dissolved in
the water also. II much less than In water nearer
the surface. The breathing apparatus OF the
deepsea fishes II modified to suit their peculiar
conditions The giil hlaments have become much
reduced In size, and In number OF Instances
mn Af fhs s.ln Nt..
all The fishes are apparently adapted to a
much emalier oxygen supply than those living
In rivers or In the shallow sea
When We think OF the vast diversity among
these hshcs. tho question arises; Are they ali
representatives. OF n single family or group that
has become specially adapted 10 life In the deep
sea; or dc they belong to different families or
Eroupsf ON. need hardly be an ichthyoiogist
to answer this question. Even currory exam.
netion OF the plates In q work on deepsea
hshcr viii show that different types are repre-
sen'cd. In fact, great many families are In.
clud"d In the dccpH.a fauna. There ar. sharks
aud rays. salmonoids. herrings. perches cells
and representatives Of many other families We
can explain this hctrrogcncity among them In
this way We may imagine that nHhoH OF many
different kinds In their search. 10 10 speak for
the unoccupied corners OF the sea, found a haven
IN these deeper waters whore they were free
from pursuit by their onomica IN the eours. OF
NW' hh'' lhrtntf anu tnrthsf INTO the
deep, change In habits taking place pari panau
With the changes In structure. Having started
out with different organizations. and possessing
different degrees OF variability. thcy became dif.
fofrntiaird IN diverse directions 80 that while
some developed enormous mouths powerful
teeth or phoHphorascont organs. others became
bottomlltinE AMI partly or completely lost their
eyes sun others developed long feol.rs for
cropping their way through the darkness Now
ahd again, however. nnhou Of separate groups
developed similar structures. 10 that there ar.
many striking eases among dcopHoa fishes OF
what the biologist calls "convorrcncc" or parnl.
lellnm.
The museum has recently prepared foi exit
billion number Of typical doopHoa nnhoH nr.
ranged In tho form Of a group The preparation
of this exhibit Involved many technical dificu
ties, such ar the modelling Of the fishes In trans
parent ~ translucent medi., 10 represent them
a. gnmorinE ar shining Ei,h tup 'porihoiea.
Considerable experimenting WIS necessary Ia