The daily morning journal and courier. [volume] (New Haven, Conn.) 1894-1907, 1895-06-12
the SLEEP OF FISHES.
Upon Somewhat Doubtful Subject.
Robert Blight in the New York Evening

Robert Blight in the New York Evening
| Post.l
We were standing on the old stone
bridge over the creek. watching the
Ispeckled trout in the stream as it
rushed along with force almost enough
to sweep man from his feet, If he att
tempted to stem the rapids. There
they WERE with noses up stream, appa-
rently as motionless as the pebbles at
the bottom of the clear water, except
that now and then they would move
first on one side and then on the other
Just a. few inches, drifting back with a
sidelong motion to their original posi-
ton. Whenever a swallow darted un-
der the bridge after the insects always
found in such places, the fish suddenly
shot out of sight from fear of the shad-
ow which fell on the water but in the
twinkling Of an eye were back again at
the same spot and in the same attitude.
was thinking deeply about the swim
ming powers which ena bled the trout to
maintain their positions in so strong
current, when my companion startled
me from my reverie with the exclama-
ton II wonder IL fish ever sleep" / jo-
| kingly replied that one, at all events,
had been known to go to bed, and Pela-
ted the experience of Otto Won Kotze-
bue, the Russian navigator, recorded
\ thus in his account Of his voyage round
| the world 1.-The nights being warm,
| we always sleep on deck to recover our
| selves from the heat of the day. a cir
cumstance which occasioned me one
night a very unexpected visit. | was
| awakened by the constant motion of a
| very cold animal at my side, which,
| when it writhed In my hand, first took
| to be a lizard, This, I thought, might
| perhaps have been brought on board at
| Chill, with the wood. But on examin-
/ ing, I found that 1t was flyingflsh
| that / had in my hands, and ] am prob
| ably the first that has caught such a.
one in bed"
| The physiology of sleep is one Of the
most abstruse questions to which the
student of life can address himself All
| that the experiments and observations
| already made have ascertained may be-
briefly summed up after this fashion.
| There Is a diminished exctabiity of the
| nerve-centers of the brain and spinal
cord so that reflex action Is in partial
allegiance, and the spinal cord in state
of partial inactivity. The only nerve
centers that do not sleep are those abso-
lutely essential to life, such as those
connected with the heart and with the
movements of respiration. Even these,
however, enjoy certain amount of re-
pose. The sleep of man is doubtless a /
recuperatiye condition, as our expert
ence testifes, and there is little doubt
that all living things need periods of
rest between periods of activity, The
consciousness of this need in ourselves
prompts the question about fishes,
whose activity and expenditure Of mus
cular force while swimming against a
torrent, must be exceedingly great.
Plants even have such periods of rest,
but they do not appear to be recupera-
tive seasons. Many flowers and some
leaves close up Under atmospheric con-
ditions, and appear to be at rest; this
however, Is not sleep. Hibernation
among animals also is not true sleep,
although it is q cessation from activity
without cessation of all vital process
es. In it there is nothing to restore lost
energy, but animals frequently come
out of the state very enervated.
The question, DO fishes sleep? be-
comes therefore, narrowed down to
this: Do they enjoy periodical rest be-
tween periods of activity, so that they
may throw off waste products and re-
pair nervous energy? In word, do |
fishes sleep like man, like the dog, who |
falls fast asleep and dreams, like the |
fowl, which you can take from the roost |
without difficulty when 1T is in q pro-
found slumber.
For a long time / kept aquaria in my |
room stocked with such fishes as | |
could safely suppose would live natu- |
rally in them, such as goldfish, min
nows and sticklebacks, in order that |
might solve the question for my own |
satisfaction, l would get up in the mid
die of the night, and hold light first |
on one side and then on another of the
different tanks, My conclusion, after
observations repeated over and over
again, was that minnows and stickle-
backs appeared to be at rest among the
weeds, but the fins moved slightly.
They did not come to the side at first,
but in few moments would emerge
from their retreats. Goldfish We're al
ways on the alert, so that more than
once I suggested that we had better
change the proverb Catch a weasel |
asleep INTO 'Catcn Sold-llSH dsleSP,
and there would be more truth in it. In
the daytime also, there were periods
when the fish showed the same phe-
nomenon. Nothing exhibited near the
tanks aroused the attention of the min
nows and sticklebacl1s, if perfect quiet
was observed. The slightest jar, how
ever, made them as inquisitive as ever.
Some fishermen will say that there
are hours in the day, if it is sultry,
when fish are not on the move. Others
will aver that there are hours during
the night when it is useless to cast a
line. Eels are on the move all night
and it is then that the eel
pots in the river are filled. The un-
sportsmanlike poaeher, who sets the
drum-net in our streams, also leaves
his engine to do its work in the night,