1832
,
THE BIOLOGY OF -FISHES
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it
we have therefore to consider} what is meantîiby
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…
That a connection exists betWeen parents and ospring is;
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one
of the most obvious things in the World, but are we]
justied in thinking that this is xed'independeny of
—
;
environment ?
Are the inheritanc‘e and environment any-L‘:
-
thing but abstractions, unreal when separated from
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another?
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”
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:
The great attraction of the heredity studies lies in the
simplicity of the method of working and the ease with whiChi— ?
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it lends itself to denite experimental investigations. Ohe "
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or two characters readin observed are studied and compared
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in parents and 08pring. From the results of the
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parison, it is assumed, the proportionate
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the paær‘itsin the Offspring can be determined. The mode
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of Ï origin and development of the characters are not
So far as the shesare c0ncerned, the on’lÿ
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Worker who has made fuse of this method has been
Schmidt, and his investigations into the nature of hefedity à
and the causes of variation --merit careful study.
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The small
Lebisies reticulaius from the
West Indies and tropical America has manÿ remarkable
characters.
It is viviparouS, and the young When born are
_
È
theadults. It becomes mature’ in three months
produce no fewer than
within
,
smmonths, the young numbering from
each time}
Moreremarkable still; ’Ône pa1r1ngw1ththemalefîS
,
Î
f0r
lottheëpëtîàtoiôabemgapparenyretamed
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,
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,
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fertlætheuecessvhdnpte offtîhe fact that1he5
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youngaremeanwherearedmtheov1duct ‘It thus pres€ähtë ;
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,
very
experiment.
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Ï To
the inner factors (inher—it,
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Schtrdt—kept two pairs with different characters
under prééiselÿ
same cute—f conditions.
The
ËÇ$ÏŒdÎCdeanh3 number of rays in the dorsal n. Inthe
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specæsthœ
a'
[f
Α 7Theone pair”
16,iït‘—he father peur
exper1mentwasrepeatedw1th twÔ.othef_gimaf ,
—