Lehrer, F. 1964 Nov. 24 - continued 1 and since these fish had evolved themselves not only into a new environment by becoming able to glide in the air but also a new host of predators, how does the flying fish know whether to dive or to become airborne? After asking myself this question, I felt that I could see fish torn between two instincts - often one would come out of the water near the ship and then dive almost instantaneously straight down into the water and disappear in the depths; I can think of no natural predators that present this constant dual environment attack on these fish; I was in the process of pursuing this problem further when a Shearwater glided by and I was obliged to jump up and grab the gun - it was then time for lunch and I turned the watch and the flying fish over to George; Binion and I took the watch again at 3:00; at 3:45 a Red-tailed Tropicbird was sighted sitting on the water far off the port beam - Mr. Ashton offered to swing the ship over in that direction, which he did and the bird was collected while it sat on the water; we learned upon dissecting the bird why it had perhaps been reluctant to fly - it had a 117cm porcupine fish in its stomach - this would not be very conducive to violent movement; at 5:45 P.M. the watch was secured; the day passed by in the usual manner, but the evening took on a new twist when four of us abandoned the second movie and played cards instead.