FISUKS OK OUR NORTH ATLAN'TIC SKABOARI3 
5 
able to transmit to the future the tend¬ 
ency to earlier change. 
THE ANADROMOUS FISHES 
Some species that help constitute the 
fisheries of the North Atlantic are an- 
adromous—that is, they spend most of 
their lives in the sea, but come into fresh 
water to spawn. Among these are the 
Salmon, the Shad, the Alewife, the 
Sturgeon, and the Striped Bass. On the 
Pacific coast the most striking instance 
of this is the Chinook Salmon, which 
ascends the Columbia River for a thou¬ 
sand miles, and the Yukon for two thou¬ 
sand, to find its spawning ground. 
How acute this instinct has become is 
shown by a Canadian experiment. Sal¬ 
mon were accustomed to run up the 
Nicola River to spawn, and at one place 
they passed an island in midstream. It 
was noted that they always took one 
channel around this island and neglected 
the other. So a dam was built across the 
channel they were accustomed to use and 
the other was left open. 
At the next run, when the fish ap¬ 
proached the barrier across the channel 
their ancestors had used in passing the 
island, not a single one of them would 
take the other channel, d’hey all turned 
back instead. 
THE eels’ spawning HABITS 
Sometimes anadromous fishes, wander¬ 
ing up rivers, get into landlocked lakes. 
Usually they do not prosper, but die out in 
their new environment. It often happens, 
however, that such anadromous fishes as 
the Branch Herring and the Salmon, get¬ 
ting into waters out of which they are un¬ 
able to find their way, so change their 
habits in the course of time that variations 
from their ancestors set in, which mark the 
beginnings of the formation of new species. 
Other fishes of commercial importance 
in North Atlantic waters have habits of 
spawning directly opposite to the anad¬ 
romous species, and,they are called catad- 
romous fishes. 'I'he true Kel is the most 
striking example of this class of fish. 
Until recently, the location of its 
spawning ground was an unsolved mys¬ 
tery of the sea. Finally a Danish expe¬ 
dition succeeded in locating it in the 
region between Bermuda and the Lee¬ 
ward Islands, where the water reaches 
the depth of a mile. 
Although they are so nearly alike that 
the layman cannot recognize the differ¬ 
ence between them, and although their 
breeding grounds partially overlap, the 
European and American species neither 
cross nor visit one another’s shores. 
The eggs are laid at depths of about 
650 feet and the larvai continue to rise 
toward the surface as they grow. At this 
stage, and until they reach their respective 
shores, they are mere bits of ribbon, so 
transparen t that the vertebrae of thei r back¬ 
bones may be counted without difficulty, 
d'he only difference yet found beween the 
European and American species is that the 
European has a few more vertebra,*. 
EELS AT THE PARTING OF THE WAYS 
Both species start out, mayhap together, 
over a route neither has traveled before. 
But when they come to the parting of the 
ways the European Elver, with a three 
years’ journey ahead of it, says good-by 
to its American cousin, which has only a 
year’s swim to get to its future home. By 
what means this unerring homing instinct 
is transferred from the parents, which 
never return, to the offsprings, that must 
travel a road they have never been over, 
is a mystery that will probably long await 
a solution. 
The spawning habits of fishes differ as 
greatly in other respects as in tho.se just 
mentioned. Some eggs are laid at the 
surface and left to their fate, with no 
responsibilities of any kind for the par¬ 
ents; others are heavy enough to sink to 
the bottom. Some fishes, like the King 
Salmon, lay their eggs on the stream bed, 
and the male covers them with gravel, 
after which male and female drift help¬ 
lessly down the stream, tail first, and die. 
THE LUMPFISH A DEVOTED GUARDIAN 
Some species, like the Sticklebacks and 
the Lumpfish, guard their eggs until they 
are hatched. I'he courage and devotion 
of the male I.umpfish to his task has 
often been noted. He eats nothing while 
guarding the eggs, but constantly fans the 
egg mass to keep it free from silt and 
bathed in flowing water. He never deserts 
his post save to drive away some intruder, 
and finally, when the eggs are hatched, 
he is a picture of exhaustion and hunger. 
The males of other species, including 
some of the common Cathshes, carry the 
eggs in their mouths until they hatch. 
