ECONOMY ”OF THE BODY—41 ,
.
“p,—:
’
_
where in the Mackerel it is elongaæd, and in the Salmon
and Pike very longand curved over the medulla. This last
condition has been associated'with the fact
predaceous shes and probably there is
cOnnectio,
but both the predaceous character and
'
,
bellum almost certainly come from their-having glarge_mouths.
_
'
-
These shes also have a conspicuous pineal _b0dy (@);{WhiCh
,
’
is hardly developed in the Herring, or Mackierel. 5 ?
,
,
shape and arrangement of the different parts : ' ’
of the“brain are determined by the inuences operating during
theearly development,when the; structures are still plastiq
’
it is probable that-the habitsand mode of life, of
'
affect the growth of the cell tissue internally in the brain
,
—
substance.
,
Thus, although
eyes and optio” lobes of the
__
'
Dog—shes are much smaller than those of the Herring,wè
'
cannot saythat the former has less keen eyesight than the
,
'
latter.
The relative abilities, in fact,’ can hardly be judged
from the external appearance of the brain, ' though
.
generally
ï accepted that the
"—
developed cerebral hénspheres is
thàt:fofçæthè…
,
_Ï,Teleost_—s_,
'
'ï
: