358 
SCANDINAVIAN FISHES. 
Exocoetus volitans, Lin., >Syst. Nat., ed. XII, tom. I, p. 520 
(ex. Gron. Zooph .); Cuv., Val., Hist. Nat. Poiss ., vol. XIX, 
p. 83, tab. 559; Steind., Slzber. Akad. Wiss. Wien, Math. 
Nsturw. Cl., LVII, i, 1868, p. 734; Ltkn, Vid. Meddel. 
Naturh. For. Kbhvn 1876, pp. 393 et 401; Mor., Hist. Nat. 
Poiss. Fr., tom. Ill, p. 481 ; Day, Fish. Gt. Brit., Irel., 
vol. II, p. 154, tab. CXXVIII. 
Exocoetus exiliens, Bl., Naturg. Ausl. Fisch., part. IX, p. 10 ; 
tab. CCCXCVII ; Cuv., R'egn. Anim., ed. 2, tom. II, p. 287; 
Swains., Nat. Hist. Fish., Amph., Rept., vol. II, p. 296; 
Couch, Fish. Brit. Isl., vol. IV, p. 128, tab. CCVII; Lillj. 
( exsiliens ), Sv., Norg. Fn., Fisk., vol. II, p. 466. 
Exocoetus (volitans?), Coll., Forh. Vid. Selsk. Christ. 1874, 
Tillsegsh., p. 177; Exoc. sp. n. ?, Ltkn, 1. c., p. 403; 
Coll., Forh., 1. c., 1879, No. 1, p. 95; Malm, Gbgs, Boh. 
Fn., p. 555. 
Ohs. The first to distinguish between more than one species of 
Flying-fish within this family was Gronovius, and the first to give 
systematic names to the two species which this author had established, 
was Linn^US, who had previously united them both under the name 
of volitans. Linnaeus made the mistake, in the twelfth edition of 
Systema Natures , of allowing his original description (in Balk’s thesis: 
Mus. Ad. Frid., p. 42 and in Amoen. Acad., vol. I (1749), p. 320) 
of Exocoetus (Halocypselus) evolans with shorter ventral fins to be in- 
cluded in the list of synonyms of Exocoetus volitans instead of Exo- 
coetus evolans, to which species according to Lilljeborg we should 
refer the type-specimen in Dpsala Museum. However, this cannot 
give rise to any ambiguity, for it is evident that Linnaeus grounded 
his opinion chiefly on the distinction drawn by Gronovius. It is less 
advisable to follow Bloch, and adopt for Exocoetus volitans the spe- 
cific name of exsiliens from Linn^us’s' Mantissa Plantarum 1771, p. 
529, for in this passage LiNNiEUS describes a young Flying-fish, as 
yet of doubtful species, “with the 1st and 2nd rays of the pectoral 
fins short,” a character which, up to the present at least, we have no 
right to regard as evanescent and belonging to young specimens. With 
respect to the limitation of the species, it is evideut from the above 
diagnosis and fin-formula that we regard it as identically the same as 
Valenciennes’ Exocoetus lineatus (Cuv., Val., Hist. Nat. Poiss., XIX, 
p. 92), the chief distinction between which and Exoc. volitans is said 
to lie in the somewhat greater number of rays in the anal fin (10 
according to Valenciennes; 10 or 11 according to Gunther, Cat., p. 
287). Lutken has shown that the white transverse band on the pec- 
toral fins may also occur in Exoc. volitans. Whether this species is 
distinct from Ranzanis’ Exoc. bahiensis (see Bleeker: Atl. Iclitli. Ind. 
Or. Neerl., tome VI, p. 71, tab. CCXLIX, fig. 2), is a question that 
must be settled by a more minute investigation of the point whether 
Exoc. volitans is always without the small teeth on the palatine bo- 
nes, and whether they are constant in Exoc. bahiensis. 
The Great Flying-fish may well be regarded as the 
most pronounced example of those singular habits which 
have given the genus its name. It is no better known 
than its kindred species; but it is probably the com- 
monest, at least in the Atlantic — and perhaps in the 
Mediterranean, where however, according to Gigli oli", 
Exocoetus Eondeletii, a near relation, is commoner. Most 
of the observations of Flying-fishes the species of which 
has not been fixed, probably refer either to this species or 
to Halocypselus evolans , also a common species. In size 
too, it stands first: the Royal Museum possesses speci- 
mens taken near St. Helena, which measure between 
about 48 and 55 cm. in length to the end of the 
inferior lobe of the caudal fin. 
Much has been written of the flight of the Flying- 
fish; and we have ascertained, chiefly from Mobius 
that it is quite different from the flight of birds or 
insects or the fluttering of a bat, and more closely re- 
sembles the leaping movements made through the air 
by the Flying Squirrels or the Flying Lizards (Dragons). 
By the help of the large and strong lateral muscles of 
the body the fish attains the speed of an arrow, which 
it maintains above the water, slackening, of course, 
towards the end, and thus traverses a distance of from 
100 to 150 metres through the air in less than 20 se- 
conds 0 . At the same instant as it leaves the surface 
of the water, the pectoral and ventral fins are expanded. 
It supports itself principally on the former fins, but 
almost passively, the wind and the pressure of the at- 
mosphere bearing the fish along without any exertion 
on its own part, save that needed to keep these fins 
expanded. There is no independent motion of these 
fins, according to Mobius; but when the wind blows in 
a direction exactly parallel to their plane, the hind 
margin flutters, like the sails of a boat in stays. The 
Flying-fish cannot steer an independent course”*, accord- 
ing to Mobius, the direction of its flight being fixed 
by the impetus once gained; and when the speed slack- 
ens, we may see its course changed by the wind, when 
the latter is not dead ahead, for some seconds before 
the fish falls back into the waves. According to Mo- 
bius the fish is hardly able to rise or descend at will, 
and when it is seen moving up and down along the 
a Espoz. Intern., Pesca, Berlino 1880, Sez. Ilal., Catal., p. 103. 
6 Zeitschr. f. Wiss. Zoo]., 30 Bd, SuppL, (1878), p. 343. 
c According to Mobius the flight seldom lasts longer than 10 or 15 seconds. 
d Each ray in the pectoral fins, with the exception of the first two, in the case of which the sinew of the extensory muscles is com- 
mon, is furnished, as is well known, with a distinct double pair of muscles. L. Agassiz, who during his voyage to Brazil, in 1865, devoted 
particular attention to the habits of the Flying-fishes in the Atlantic (see A Journey in Brazil, p. 522), denies that the Flying-fish is en- 
tirely destitute of the power of altering the plane of the expanded fins by means of these muscles and thus rising or falling during its flight, 
or that it is quite unable to change the direction of its course by bending its body. Even Mobius acknowledges that it often happens that 
Flying-fish which are just above the surface, alter their course by meaus of the inferior lobe of the caudal fin, which then hangs down in 
the water. 
