SOME ASPECTS OF PHOTORECEPTION A N D VIRION I N FWIIES
189
(1958). One important idea which has come of this work and one whioh
has been emphasized by some of the workers concerned, is that the
visual pigments, of marine fishes at least, are adapted to the quality of
light in their environment. There are considerable differences in the
extent to which attenuation of different wavelengths oocurs in natural
wutore. 111 const:tI wittttrs whero thero i H much suqmnded matter and
dissolved yellow substance, the water is green and maximal tramparency lies in the region of the spectrum between 500 and 600 mp, as
does that of fresh waters. A set of normal transmission curves for
lo-'
I
425
450
475
500 525
Wavelength
Fro. 8. Relative spectral curves of transmitted daylight at doptha shown in the b y of
(Reproduced with per.
Biscay (46"29'N, 7"59'W, 10.30-11.30 h, 26 September).
mission from Boden ct al., 1960.)
different types of coastal waters, with rather flattened maxima between
500 and 570 mp, is given by Jerlov (1951). To waters with these spectral
qualities, the rhodopsins and porphyropsins of inshore, estuarine and
anadromous species appear to be well suited, at least aa regar& their
absorption characteristics at wavelengths between 500 and 636 rnp
(Munz, 1958b). Clear owanic water8 arc blue, and hnvo maximal
transparency in thc region 400 to 800 mp. With incrsming dopth, there
is preferential nhorption of Nhort m d lorig wnvnlongthH tmlow and
~ h o v o tho Iduc~-gr(w rcgioii of tho Hpcctrunl, nrid tho ronidud light
which rc!aclion c l o q w wator lioH in tho rogion twoiirid 476 to 480 mp
(Ng. H) (Jorlov, I9fi I ; I M o n cl i d . , I WO). 'I'huro is obviolur biological
189
(1958). One important idea which has come of this work and one whioh
has been emphasized by some of the workers concerned, is that the
visual pigments, of marine fishes at least, are adapted to the quality of
light in their environment. There are considerable differences in the
extent to which attenuation of different wavelengths oocurs in natural
wutore. 111 const:tI wittttrs whero thero i H much suqmnded matter and
dissolved yellow substance, the water is green and maximal tramparency lies in the region of the spectrum between 500 and 600 mp, as
does that of fresh waters. A set of normal transmission curves for
lo-'
I
425
450
475
500 525
Wavelength
Fro. 8. Relative spectral curves of transmitted daylight at doptha shown in the b y of
(Reproduced with per.
Biscay (46"29'N, 7"59'W, 10.30-11.30 h, 26 September).
mission from Boden ct al., 1960.)
different types of coastal waters, with rather flattened maxima between
500 and 570 mp, is given by Jerlov (1951). To waters with these spectral
qualities, the rhodopsins and porphyropsins of inshore, estuarine and
anadromous species appear to be well suited, at least aa regar& their
absorption characteristics at wavelengths between 500 and 636 rnp
(Munz, 1958b). Clear owanic water8 arc blue, and hnvo maximal
transparency in thc region 400 to 800 mp. With incrsming dopth, there
is preferential nhorption of Nhort m d lorig wnvnlongthH tmlow and
~ h o v o tho Iduc~-gr(w rcgioii of tho Hpcctrunl, nrid tho ronidud light
which rc!aclion c l o q w wator lioH in tho rogion twoiirid 476 to 480 mp
(Ng. H) (Jorlov, I9fi I ; I M o n cl i d . , I WO). 'I'huro is obviolur biological