Image from the Biodiversity Heritage Library.
Contributed by Museum of Vertebrate Zoology, University of California, Berkeley.
| www.biodiversitylibrary.org
Transcription
to dig out each one. Greenie was glad to see her and came closer, still
in a low branch of the tree. Brownie joined him there and they talked
a little, then dropped to the ground, Greenie puttering about Brownie
going to examine her two favorite branches in the cage puttering about
for a few minutes, when Brownie decided to investigate the worm situation
again. I did not offer her any, but held the box beneath my hands in
my lap where she would be compelled to stand almost on her head
to get them. She tried every possible angle, gripping my fingers and
hands with her sharp claws which left white scratches all over the
back of my hands when she slipped, as she frequently did, until she dis-
covered the only practicable position was head straight down and tail
straight up under my chin. In this way she got all the worms and, after
sampling a button, retired for a nap 10 feet away.
During this her eyes would close slowly and remain closed for a time,
then open at some sound, and sometimes remain partially closed for
a considerable length of time. I watched them closely with glasses
magnifying 3½ diameters, thus making the bird appear somewhat less than
3 feet away. The head of the bird was in a bright beam of sunlight.
It soon was evident that both eyelids are movable. I watched for
very slowly
about ten minutes, during which time the lids were moved many times.
The lids are capable of independent movement. In closing the eye,
first
most of the time the lower lid rises what appears next and it
may or may not be followed by a corresponding movement of the upper lid.
The line of closure may be anywhere, that is: across the pupil, above it,
or below it. This fact alone shows that both lids must be movable; but
in addition the movement of the upper lid is also easily seen . It is,
in fact, frequently moved, as in winking, without the lower one moving
at all. These birds wink often, but until now I have not been positive
that it was not the nictitating membrane that was concerned, although
I had frequently noted in the past that they seemed to wink like mammals
that the "wink" came from above and that whatever it was that moved, it