644 Do Flying Fish Fly ? [ September, 
has not, so far as I am aware, been determined by actual observa- 
tion. Most observers are of opinion that these singular creatures 
glide up the wind, and do not beat it after the manner of birds; 
so that their flight (or rather leap) is indicated by the arc of a 
circle, the sea supplying the chord.” 
From a careful examination of the structure and action of 
these fins, Pettigrew has been able to satisfy himself that “they 
act as true pinions within certain limits.’ That this restrictive 
phrase, “within certain limits,” is intended to exclude a flap- 
ping motion, is evident from the following: “The flapping 
and gliding action of the wings constitute the difference between 
ordinary flight and that known as skimming or sailing Hight. 
The flight of the flying fish is to be regarded rather as an exam- 
ple of the latter than the former, the fish transferring the velocity 
acquired by the vigorous lashing of its tail in the water to the 
air.” . r 
_ Pettigrew shows that all kinds of wings, when extended in 
flight, have a kite-like action, or a “ combined parachute and 
wedge action” independent of any beating movement; and it iS 
to this action alone that he refers when he says the pectorals “act 
as true pinions wt/in certain limits.” ; 
According to Pettigrew, “ Mr. Swainson, in crossing the line in 
1816, zealously attempted to discover the true action of the fins 
in question ; but the flight of the fish is so rapid that he utterly 
failed.” So much for the negative testimony. $ 
In favor of the flapping motion of these fins, we have the testi- 
mony of Capt. de Freminville! who says, “ I have been able to 
convince myself that they [flying fish] do actually fly, impressing » 
upon their fins, which serve them as wings, a rapid movement—4 
species of vibration [frémissement]—which sustains them and 
causes them to advance through the air.” . 
Speaking of these fish, which he saw on the way’ from Callao 
to Lima, U. de Tessan? says: “J'ai très-bien vu un poisson- 
volant battre d'abord des ailes en l'air, et puis les faire vibrer €n 
planant. a 
In the “ Reise der Oesterreichischen Fregatte Novara um die. 
Erde” (1857-1859), published by Wiillerstorf-Urbair, 1861, P. 
109, occurs (according to Möbius) the following: “Care ul ob- 
1 Ann. des Sci. Nat., Vol, XX1, p. 102, 1830. 
2“ Voyage autour du Monde sur la Vénus,” Parjs, 1844. 
