650 Do Flying Fish Fly? |September, 
testimony out of court by the mere breath of his private opinion. 
Surely this is a most facile mode of reconciling contradictory 
testimony ! 
If Mobius merely announces it as his opinion that the tremu- 
lous movement observed in his experiment is identical with the 
movement that has been so often interpreted as a true flying 
movement, then we have simply to raise objections. 
There are three questions here to be considered: First, whether 
the fins probably exhibit such movement; second, whether such 
a movement, if made, would be probably recognized; and third, 
whether, if recognized, it would likely deceive “ good observers.” 
It would seem that the wings of a sailing bird, such as a gull 
or a hawk, would be quite as likely to exhibit such motion as the 
fins of the flying fish; and it would be much more easily recog- 
nized in the former than in the latter. 
With reference to this point, I watched the long-winged gulls 
that were seen almost every day of our voyage. These birds 
were often circling about the stern of the boat, on the watch for 
waste bits of food, and were remarkably good skimmers, moving 
the most of the time without flapping the wings. I very rarely 
saw any vibratory movement that could be attributed to the wind 
alone, and ever anything of the kind that was of more than a 
momentary duration. It is very evident that, under conditions 
that would render possible a continuous movement of this kind, 
the bird, as well as the fish, would inevitably fall to the water. 
Is it probable that a momentary quiver in the comparatively 
small fin-wings of a swiftly-moving flying fish would be noticed ? 
The fact that no naturalist has ever affirmed anything of the kind 
except Mobius, who bases his assertion on an experiment with 
an alcoholic specimen, is sufficient answer to this question. 
_ As to the probability of any one being deceived by such 
motion, I cannot, of course, judge from experience, as I have 
never been so fortunate as, in the first place, to detect it, and, in 
the second place, to discover that I had erroneously interpreted 
it. I cannot persuade myself, however, that any “good observer 
would be likely to make such an egregious blunder. 
That Mobius does not regard this hypothetical quivering as '" 
any sense a true flying movement, he states in the most unequivo- 
cal manner, and goes on to ask, “ how, then, are the Exoccetl 
able, without touching the water, to rise over the waves? ro o 
