HARD WfCKE'S SCIENCE- G OS SIP. 



245 



salt provisions, and, indeed, most excellent eating, for 

 those who do not mind bone. 



It is rare not to find a few on the decks in early 

 morning, that have come in over the gangway, a 

 height of seven feet above the water-line. They often 

 fly higher than this, as many a fair traveller in a mail 

 steamer can tell who has been startled at dead of 

 night by the flopping of a flying-fish through a port 

 into the sanctity of her state-cabin. 



As regards the much debated question of their 

 flight. After carefully observing them for some time, 

 I have come to the conclusion, that their great 

 pectorals are never by any chance used to strike the 

 air with. I have come to this conclusion, not only 

 from watching them from various points of view, but 

 also from dissection, and their so-called flight is 

 nothing but a series of prodigious leaps. Let us look 

 for a moment at the movements and structure of these 

 wing-like fins. At rest they are closed, the flat 

 surfaces looking inwards and outwards, and their 

 direction backwards and slightly upwards. 



As the wing is brought forward the rays are spread 

 out, and the internal and external surfaces become 

 superior and inferior, the first and longest ray fore- 

 most. The wing is continued forward in this position 

 to a little beyond the right angle, when it is turned, 

 in order to strike the water either directly backwards, 

 or backwards and upwards. The extremity of the 

 fully extended wing is also bent backwards, giving it 

 the appearance of a scoop, and thus we see what an 

 immense power there is for grasping the water and 

 throwing it backwards. On leaping simply to get 

 clear of the ship they make one or two vigorous 

 strokes, and with their wings in the position of rest, 

 pass through the air for a few yards and then fall. 

 It may also be noticed that they strike the water as 

 they enter it. When being pursued, however, they 

 can cover a distance of over one hundred yards of 

 space. This, with nothing to help them but the 

 original stroke or strokes, would be impossible. In 

 these long flights it can be seen, and I have found, 

 standing with my eye as nearly on a level with the 

 ■water as possible the best, watching them as they go 

 away from me, that their wings are spread out to 

 their full extent, with of course their flat surfaces 

 superior and inferior, and there is no doubt that in 

 this position they act after the manner of a parachute. 

 But often this cannot be of much service to them, as 

 they frequently go dead "in the wind's eye." I 

 believe that there are two ways by which they 

 progress : one, by giving a vigorous stroke with their 

 wings — hitting the water precisely as they do in 

 swimming — on coming to the summit of a wave ; by 

 this they are again raised into the air and propelled 

 forwards. The other way is by a stroke of their tails, 

 by which they not only propel themselves forward, 

 but also are enabled to change their course. 



This latter method is very similar to the movements 

 of their relation the gar-fish. The latter I had a 



good opportunity of observing the other day when 

 lying at anchor in Aden harbour. An immense 

 shoal of small fish (species ?) were disporting them- 

 selves round our stern, and at a short distance from 

 them, several gar-fish were swimming slowly to and 

 fro, waiting an opportunity to seize their prey. At 

 first it was a matter of wonder that they did not 

 at once make a dash for a fish, but it soon became 

 evident that the little ones when prepared, were too 

 fast for them. On the outside of the shoal, were 

 numerous fish of the same species, but of a very much 

 larger size, giving one the idea of forming a body- 

 guard ; this idea was soon dispelled, by seeing that the 

 gars treated them with the greatest indifference, as 

 they in turn were treated — the reason no doubt 

 being that the garfish, unlike some young friends that 

 I have met, have eyes in proportion to their stomachs, 

 and find that the bigger fish would prove a serious 

 difficulty if an attempt were made to swallow them. 

 The lucky gar who had seized a toothsome morsel, 

 often became an object of envy and hatred to his 

 brother fish, who pursued him with sinister designs. 

 It is then that the pursued, raising the anterior two- 

 thirds of his body out of water, dashes along at terrific 

 speed for many yards, creating great disturbance in 

 the water, and as he is never followed far whilst 

 performing this feat, it is probable that the splashing 

 of the water renders him invisible to, or confuses his 

 pursuer. 



To return again to the flying- fish ; we find that the 

 wing is not capable of the movements necessary to 

 propel the fish through the air. It is true it is 

 capable of being moved up and down, though not 

 above the horizontal, and of course, if the wings were 

 used in this way, and had sufficient strength, which 

 I doubt, it would cause the fish to rise in the air; 

 but it is apparent to the most cursory observer that 

 they never do this. As for progression forwards, 

 I have before stated that the wing cannot be abducted 

 beyond a right angle, and the only movements that 

 can be brought about are striking directly backwards, 

 or backwards and upwards. 



There is at once a striking difference in formation 

 between this great fin and the wing of a bird. The 

 latter has anteriorly and laterally the strong bones of 

 the wing itself and the long primary feathers, which 

 are first brought forward to cleave the air, and the 

 power of flight is almost solely due to this, for the 

 same action in the fish the fin would have to be 

 rotated forwards 45 ; a feat impossible alike from the 

 structure of the joint, and the action of the muscles 

 covering it. It is worthy of notice that these fish 

 have an oval swim-bladder capable of enormous 

 distension, nearly filling the abdominal cavity at the 

 expense of the other organs. 



These are the ideas that I have formed concerning 

 the locomotion of the Exocceti, but to speak with 

 absolute certainty of a subject so difficult of exact 

 observation would be most rash, and as for many 



