On the Flying-fish Problem. 327 



However, furtlier division of tlio, Me'^ozoic Rhynclioncllids 

 is imperativo, if only for the sake of cla.ssificatory conve- 

 nience ; for the present genus is quite unwieldy, and therefore 

 very troublesome for any systematic arrangement. 



Summary. 



[New names in heavy type.] 



Cleiothyridina, = Cleiothyris, auctt. 



C'leiot/ii/rix, 1841, = T. concentrica series. 



Cumposita, 1845, = Seminula, auctt. 



Ci/chthyns, 1844, = T. lotissima series. 



J'jpithyriK, 1 84 1 , = T. tna.dllata series. 



L))it/ii/iis bathonica, = T. ina.iillata (pars). 



Hypothyridina, = Hypothyris, auctt. 

 liypothyris, 1841, preoccupied. 

 Leptodus, 1883, precedes Lytfonia. 

 Lyifonia, 1883, syn. of Leptodus. 



Seminula, 1844, = Camarophoria (pars). 



XLV. — The Flying-fish Problem. 

 By Lieut. -Colonel C. D. Durnfokd, 



In a paper published in these 'Annals' for January 1906 

 tl)e impossibility, from a mechanical point of view, of a 

 fiying-fi:vh accomplishing sailing flight was shown. The 

 argument was based upon the fact that as a flying animal 

 the flying-fish is equipped with wings of a fractional sailing 

 value compared with those of a sailing bird. Also that if 

 the wings were many times larger, so as to bring the fish on 

 an equality with the bird in this respect, it could only sail 

 with the bird's limitations as regards direction of the wind, 

 and with the bird's frequent assistance from rowing flight. 

 Also that if the figures (which can be easily verified or, if 

 wrong, refuted) are correctly given in the article, the 

 accepted aeroplane flight is miraculous, unless a new law of 

 Nature be discovered. 



It is, then, perhaps advisable, if the present curious con- 

 dition of the question is to be understood, to examine how it 

 has come about. 



The flying-fish problem is a very odd one in many ways, 

 of which the most striking is the unexplained power therein of 

 the negative to quench the positive. Throughout we find the 

 aeroplanist's '' I cannot see the wing-movement" smothering 

 a fairly equal bulk of '' I can, and have, and do see it." 



Let us create a parallel instance, for a real parallel does 



