-
;
,
to
_
Dayhgl .
_
‘;
.,
;
.
4.45
,
,
—:
__
.
_
_
.
—
7.55'
‘
'
-
.
_
to
'.Dusk=
—
9.17
_
‘
,
p.111°
,
,
,
.
Surface.
28 ft.
46 ft.
'
63 ft.
100 ft.
’
Pl. 49.
-
] 129.
-
'
Vertical Distribution of Plankton Animals in July.
(p. 128).
.
,
Showing how in the daylig_ht the surface waters are poorly populated, but at
'
_.
dusk they become lled up by theupward migration of animals from deepe’r levels.