Fig. 2. (A) Iridophores of the `red' stripe of A. subulata superfused with
50 µmol l-1 acetylcholine (ACh). (a) Before superfusion, (b) 20
s after start of superfusion, (c) after 1 min. The `red' stripe iridophores
change from non-reflective to reflective upon perfusion with ACh and become
non-reflective after washing with ASW. (d) 5 min after washing, (e) 9 min
after washing, (f) 12 min after washing. (B) Reflective `red' stripe
iridophores of A. subulata at 45° incidence. Reflectivity is best
in the green parts of the spectrum. Photos are taken at 1 min intervals.
Reflections gradually shift from green (a) to red (f) before switching off
completely (not shown). (C) Video images of A. subulata at an angle
of approximately 45° to the `red' stripe. (a) Shortly after capture the
`red' stripe was strongly reflective in the blue-green. (b) After
approximately 15 min the reflectance changed to green. (c) After 30 min the
`red' stripe reflected yellow-green light, with some red in the ventral parts
of the stripe. (D) The `blue' stripe of A. subulata superfused with
50 µmol l-1 ACh. (a) Before superfusion the `blue' stripe is
reflective. Following ACh superfusion it becomes gradually non-reflective. (b)
After 15 s, (c) after 1 min, (d) after 1.5 min, (e) after 2 min, (f) after 3
min. (E) The iridophores of the ventral side during ACh superfusion (50
µmol l-1). (a) Before superfusion the iridophores are weakly red
reflective. In response to ACh, reflections shift gradually towards the orange
and yellow parts of the spectrum. (b) After 1 min of perfusion, (c) after 1.5
min, (d) after 2 min.