ICHTHYOLOGY. 



^lalacop- 



Abd<imi- 



nales. 

 Ksiicitiu?. 



Esox saurus, Bl. Sch. pi. Ixxviii. 2, and is also found along 

 the British shores, where it is known under the name of 

 Egyptian herring. It sometimes leaps so actively out of 

 the water as to pass over a space of thirty or forty feet. 

 Of the nearly allied genus Hemi-rami'hu.s, Cuv. several 

 species are to be found in the warm latitudes of both he- 

 mispheres. Although their flesh is oily, it is of an agree- 

 able taste. 



We now come to a tribe of fishes which have attracted 

 much attention, owing to the power they possess of leap- 

 ing to a great height into the air, and even sustaining 

 themselves in Uiat element for a perceptible time. This 

 faculty, which has caused them to be nameA Jiying fishes, 

 they owe to the excessive development of their pectorals, 

 a peculiarity which readily distinguishes them from all 

 other abdominal fishes. Their head and body are clothed 

 with scales, and a longitudinal series of carinated scales 

 forms a salient line at the bottom of each flank, as in 

 some of the genera last described. The head is flattened 

 above and on the sides ; the dorsal is placed above the 

 anal, the eyes are large, the inter-maxillaries without pe- 

 dicles, and themselves forming the edge of the upper jaw. 

 The two jaws are furnished with small pointed teeth, and 

 the pharyngeal bones with teeth en pave. Such as pre- 

 sent these characters are to be referred to the 



Genus Exocetus, Linn., a name which signifies lying 

 out, and which was given by the ancient Greeks to a fish 

 that was reported to be in the habit of coming to repose 

 on shore. They are further characterised by having ten 

 branchial rays, a very large swimming bladder, and straight 

 intestines without ca?ca; the upper lobe of the caudal fin is 

 the shortest. 



The Exocetus voUtans, Bloch, 398 (see Plate CCCIV. 

 fig. 11), is a well-known flying fish of the ocean (but not 

 to be confounded, as it has sometimes been, with the 

 Trigla volitans, or flying gurnard, already alluded to under 

 the genus Dactylopterus). It is common in many of the 

 warmer parts of the northern hemisphere, especially be- 

 tween Teneriffe and the line. It is also said to occur oc- 

 casionally in the Mediterranean, and may be recognised 

 by its large eyes, and the smallness of the ventral fins, 

 which are placed in advance of the centre of the body. 

 Its mouth is slightly tubular, its scales deciduous, and its 

 size from six to twelve inches. A species more common 

 in the IMediterranean is the E. exilie/is, Bloch, 397, of 

 which the ventrals are long, and placed behind the centre 

 of the body. It attains to the length of fifteen inches. 

 The young have black bands upon the fins. 

 !■ Some difference of opinion seems still to exist in regard 

 to the mode of flight in these fishes. Mr Bennet sup- 

 poses, that because they do not use their pectoral fins in 

 the air precisely as birds use their wings, that their pro- 

 gression ought rather to be termed leaping than flying. 

 " In fish," he observes, " the organ of motion for propel- 

 ling them through the water is the tail, and the fins di- 

 rect their course ; in birds, on the contrary, the wings 

 are the organs of motion, and the tail the rudder. The 

 only use of the extended pectoral fins in the fish is for the 

 purpose of supporting the animal in the air, like a para- 

 chute, after it has leaped from the water by so?ne power 

 which is possessed even by the whale. From the struc- 

 ture of the fin, I cannot consider it at ail calculated for 

 repeated percussions out of the water ; while in that fluid, 

 it continues its natural action uninjured ; but it soon dries 

 when brought into contact with the air, and the delicacy 

 of the membrane between the rays would very readily 

 become injured were the organ similarly exerted in that 



medium. The greatest length of time that I have seen 

 these I'olatile fish on the fin, has been thirty seconds by 

 the watch. ...Their usual height of flight is from two to three 

 feet ; but I have known them come on board at a height 

 of fourteen feet ; and they have been well ascertained to 

 come into the channels of a line-of-battle ship, i. e. as 

 high as twenty feet and upwards. But it must not be 

 supposed that they have the power of elevating them- 

 selves in the air, after having left their native element : 

 on watching them, I have often seen them fall much be- 

 low the elevation at which they first rose from the water, 

 but never in any one instance could I observe them raise 

 themselves above that height. I therefore regard the 

 elevation they take to depend on the power of the first 

 spring or leap they make on leaving their native element."' 

 Colonel Bory St Vincent, on the other hand, regards that 

 opinion as erroneous which limits their aerial movements 

 to a single sudden spring. " Je n'ai pas vu les exocets 

 s'^lever tres-haut ; mais je souvent observe qu'ils ne se 

 replongeaient dans la mer qu'a une bonne portee de fusil 

 au moinsdu point d'ou ilsetaient partis. Selon I'occasion, 

 ils changent la direction de leur vol, et s'abaissent ou 

 s'elevent parallelement aux flots agites ; ils ont enfin la 

 faculte de voler d'une maniere bien plus parfaite qu'on ne 

 la leur suppose generalement."^ The double chase of this 

 unfortunate species was indicated by Duquesne so far 

 back as 1690. " Ce petits animaux," observes that voy- 

 ager, " n'ont nul repos, ni dans I'eau, ni dans fair; dans 

 I'eau, a cause des bonites, dans fair, a. cause des oiseaux 

 qui fondent sur eux avec plus de rapidite que le faucon 

 ne fond sur la perdrix."^ Indeed, all voyagers, whether 

 ancient or modern, have recorded the delight with which 

 they witnessed these sudden emergencies ; and Bosc in 

 particular describes the flying fish as sometimes rising in 

 hundreds, and even thousands, around his vessel, and dart- 

 ing over the waves in all directions, scouring away, as 

 Coleridge has beautifully said in relation to another group 

 of animals, " like a Tartar troop over the wilderness." 

 We shall conclude this notice by observing that the flesh 

 of flying fishes is savoury and delicate, and that they thus 

 present another claim to the attention of the voyager. 



At the end of the family of the Esocid^ is to be placed 

 a genus which differs but a little from them, except in 

 having long intestines provided with two C£Eca, and which 

 will probably be formed into a particular family. 



Genus Mormybus, Linn. Body compressed, oblong 

 and scaly ; tail slender at the base, and enlarged towards 

 the fin ; head covered with a thick naked skin, envelop- 

 ing the opercula and the branchial rays, and leaving for 

 their aperture only a vertical cleft, a circumstance which 

 has caused some naturalists to deny the existence of 

 opercula, although they are as complete as in any other 

 fish, and to assign to them only two branchial rays, al- 

 though there are five or six. I'he opening of the mouth 

 is very small, almost as in those Mammalia named ant- 

 eaters, and the maxillaries form its angles. The teeth, 

 which are slender and notched at the end, cover the in- 

 ter-maxillaries and the lower jaw ; while on the tongue, 

 and under the vomer, there is a band of small and crowd- 

 ed teeth. The stomach is in the form of a rounded sac, 

 followed by two cajca, and a long slender intestine al- 

 ways enveloped in a profusion of fat. The bladder is 

 long, large, and simple. Many of these fishes inhabit the 

 Nile, and they are ranked among the best which that 

 river produces. It is conjectured that it was one of them 

 which the ancient Egyptians held in religious veneration, 

 and which they named oxyrhincus. 



201 



Malacop- 

 tervpii 



Abdomi- 

 nak's. 



Ksocuiae. 



* Wanderingt in New South TValcs, &c. vol. ii. p. 31. = Voyage aux quatre Ues d'Afri^ue^ t. i. p. 83. 



* yoyage aM.r Indcs Orieniaks, t. i. p. 236*. 

 VOL. XII. 2 C 



