Series 1. Order G. PLECTOGNATIII. 315 



intestine is of uniform width, and without coeca; and their air-bladder, tliough slender, is 

 large in proportion to their size. They form two genera ; and the lirst admits of subdivision. 

 Syngnaihus. — These are characterized by a tubular snout, composed, as in the Fistularida;, of pro- 

 longations of the ethmoid, vomer, temporals, pre-operculum, and other bones ; and tliis snout ends in a 

 mouth as in other fishes, only its opening is nearly vertical. The gill-opening is near the nape ; and 

 there are no ventral fins. In their reproduction there is this peculiarity, that the eggs slide into a 

 pouch formed by an inflation of the skin, and remain there till they are hatched. This pouch is under 

 the beUy in some, and at the base of the tad in others. It bursts spontaneously, and allows the fry to 

 escape. [Thus these fishes have some analogy to the marsupial IMammalia.] 



Sijngnathus, the Pipe-fishes, properly so called, have a very long and slender body, difFering; little in diameter 

 throughout its entire length. Some have a dorsal, caudal, and anal ; others want the anal only, and in these the 

 hatching-pouch is situated under the tail. S. aciis, the Great Pipe-fish, and S. tylphe, the Peak-nosed Pipe-fish, 

 both found in the British Seas, belong to these sections. Others, again, have neither anal nor pectorals ; and 

 others no fin but the dorsal. S. opiiidion, the Snake Pipe-fish, and S. lumhricifonnis, the Worm Pipe-fish, are 

 British fishes belonging to these sections. [They have the pouch under the belly ; and it is to be observed that in 

 all the species it is the male, and not the female, which has the pouch, and hatches the eggs.] 



Hippocampus, has the body compressed laterally, and much more elevated than the tail ; and in dead speci- 

 mens the neck bends, and the upper part has a faint resemblance to the head and neck of a Horse in miniature, 

 from which they have been called Sea-horses. The margins of their scales are formed into ridges, and the angles 

 into spines. They have no fin in the tail, but that organ is prehensile, and enables them to climb or hold on by 

 the stalks of marine plants. The common species is found in tlie British seas, and is sometimes about five inches 

 long ; and, on the coast of Australia, there is a longer one, with the angles of the scales extended into leafy 

 appendages. 



Soleiwstomus, differ from the former chiefly in having, behind the pectorals, large ventrals united with each 

 other and with the body, and forming an apron which serves to retain the eggs while hatching, in the same 

 manner as the pouch of the Pipe-fishes. There is cue dorsal of few rays near the nape, a very small one near the 

 tail, and a large pointed caudal, but otherwise they resemble Hippocampus. The only known species is from the 

 Indian Ocean. 



Pcffasiis, have a snout as in the former, but the mouth under it, and moveable, like that of a Sturgeon, only 

 composed of the same bones as in other osseous fishes. The body is armed as in Hippocampus, but their thorax 

 is broad, depressed, and with the gill-openings in the sides. They have two distinct ventrals in rear of the pecto- 

 rals, which are often large, and have procured these fishes the name of Pegasus, or Flying Horses. The dorsal 

 and anal fins are opposite each other, the abdominal cavity is wider and shorter than in Syngnathus, and the in- 

 testine has two or three flexures. Some species are found in the Indian seas. 



THE SIXTH ORDER OF BONY FISHES. 



PLECTOGXATHI (Fishes with Soldered Jaws). 



Though retaining many of the characters of the Bony Fishes, the members of this order re- 

 semble the Cartilaginous ones, in the imperfect structure of the jaws, and the slow ossification 

 of the skeleton; but still this skeleton is fibrous, and resembles that of the Bony Fishes. The 

 chief characters are — the maxillary soldered to the side of the intermaxillary, which consti- 

 tutes the jaw, and the connexion of the palatal arch with the cranium by an immoveable 

 suture. Besides, the gill-lid and rays are concealed under the thick skin, with oidy a small 

 opening, the ribs are mere rivets, and there are no true ventrals. The intestine is large, and 

 without coeca; and the air-bladder is always ample. They admit of division, by the character 

 of their teeth, into two very natural families. 



THE FIRST FAMILY OF THE PLECTOGNATIII. 

 Gymkodontes (Fishes with naked Teeth). 

 Instead of teeth, these have the jaws covered with a substance like ivory, laminated internally, and 

 resembling the beak of a Parrot, though these are true teeth united, and are reproduced as soon as tlicy 

 are destroyed by using. Their gUl-lids are small, with five obscure rays. They live on Crustacea and 

 sea-weed, and their flesh is mucous, and not liked,— that of some species being reckoned poisonous, at 

 least at certam seasons of the year. 



