4 o6 SPINY-FINNED GROUP. 



by the pelvic fins consisting of six soft rays. The greatly elongated body is either 

 covered with very small scales, or naked ; the teeth are small ; the first dorsal, if 

 present, is formed of small isolated spines ; the soft dorsal and anal are of moderate 

 length; the pelvic fins consist of six rays, without any spine, and are separated 

 from the pubic bones, which remain attached to the pectoral arch ; and there are 

 five branchiostegal rays. The air-bladder is large, and the vertebrae are very 

 numerous, those in the anterior part of the column being fused into a continuous 

 tube, as in the flying gurnards. These fishes, which may be regarded as gigantic 

 and highly specialised marine sticklebacks, frequent the coasts of the tropical and 

 subtropical portions of the Atlantic, Indian, and Pacific Oceans, some of them 

 growing to from 4 to 6 feet in length. In the genus Fistularia, the body is 

 naked, the forked caudal fin has one or tw^o of its middle rays produced into a 

 long, whip-like filament, and there are no isolated spines to the dorsal fin. The 

 species are confined to the Tropical Atlantic and Indian Oceans. On the other 

 hand, in the typical genus Aulostoma the body is covered with small scales, the 

 caudal fin squared, and without filaments, while the back carries a series of small 

 isolated spines, and the teeth are rudimentary. In this genus the species inhabit 

 the Atlantic ; but the third genus (Auliscops) is represented by a single form from 

 the North American Pacific coast, distinguished by the naked body, the thoracic 

 position of the pelvic fins, and the presence of numerous spines in front of the 

 dorsal fin. Day states that he found the Indian species of Fistularia, which is 

 common at Madras, frequenting the most muddy localities. 



Trumpet-Fishes, While agreeing with the flute-mouths in the production of the 

 etc - muzzle into a tubular beak, the two genera of fishes constituting the 

 family Centriscidce differ by the imperfect development of the pelvic fins, which 

 are truly abdominal in position. They have two dorsal fins, of which the spinous 

 one is short, while the soft one is similar to the anal. Teeth are wanting. The 

 family is distributed over the Atlantic, Mediterranean, and Indo- Pacific, the 

 common trumpet or bellows fish (Centriscus scolopax) occasionally making its 

 appearance on the south coast of England, while it is also known from such a 

 distant region as Tasmania. It belongs to a genus characterised by the oblong or 

 elevated and compressed body being covered by small rough scales, with some 

 bony strips on the back and under surface, the absence of a lateral line, and the 

 length of the spines of the 'first dorsal fin. The second genus, Ampliisile, differs by 

 the elongate form of the compressed body, which is covered on the back with a 

 cuirass of bony plates, behind which are the two dorsal fins. This genus is 

 confined to the Indo-Pacific; and in the Indian A. scutatct the dorsal armour 

 terminates behind in a long spine, close beneath which are the three spines of the 

 first dorsal fin, followed by the second dorsal, the caudal appearing on the lower 

 surface of the body just behind the anal. Dr. Gtinther writes that in these 

 tortoise-fishes, as they may be called, the " body is so thin that it has the appear- 

 ance of being artificially compressed between two sheets of paper; it is semi- 

 transparent, especially in the region of the air-bladder. The structure of the 

 vertebral column is extremely singular, and unique among Acanthopterygians. 

 The trunk portion is more than four times as long as the caudal, nevertheless it 

 is composed of only six vertebrae, whilst the latter consists of fourteen." The 



