FISHES. 265 



captives, attach themselves, and are hauled in, securing the fish for their master. The 

 fact of their use in this way had been known long before ; but no original account 

 thereof had for a long time appeared. When not in use, the fishes are mostly kept 

 in small canoes or wells of water, and come to the surface on the approach of the 

 fisherman ; and they have learned to allow themselves to be taken from the water, 

 and submit to being handled without attempting to plunge or break away. The 

 owners are said to call them with a whistling sound, but whether they obey such a 

 call or not has not been sufficiently verified. 



The most common of the Echeneididids are the Echeneis neiicrates, a slender species 

 with nineteen to twenty-five laminaj in the disk, and liemora squahpeta or remora, 

 a short fish with eighteen or nineteen lamince in the disk. 



Sub-Order XII. — T^niosomi. 



There are certain forms remarkable for their very compressed form, known popu- 

 larly as ribbon-fishes, which differ much from other fishes, or, at least, present so few 

 indications of affinity to any one group, that provisionally they may be segregated 

 into a sub-order named Tteniosorai. The typical representatives of the group are des- 

 titute of an anal, the dorsal is very long, and its foi-emost rays elongated and segregated 

 in a distinct portion or nuchal fin, 

 and the caudal is rudimentary or 

 excentrically developed ; the ven- 

 trals ai-e thoracic. There are two 

 families. 



' The Trachypterid^ are fishes 

 provided with elongated ventrals 

 of several rays, and destitute of 

 ribs. The species are of uncertain 

 number, but there appear to be 

 two European ones : a northern 



species, Trachypterus arcticus, and j,,^ j^^ ^^^^^^^T^hypurus. 



one living in the Mediterranean, 

 the Ti'uchyptenis iris. They are said to attain a length of about ten feet, 

 although the average size must be considerably less. In fact, the largest speci- 

 men obtained in the British seas was only seven feet nine inches long. They inhabit 

 deep water, and only appear to voluntarily approach the coast in autumn, when they 

 are at rare intervals taken in herring nets. Most of the specimens examined by 

 ichthyologists have been thrown up on beaches by storms. They are said to some- 

 what resemble flat-fishes in their movements, and to swim sideways, with one side 

 turned obli(juely upwards. Dr. Day records that " the Finland fishermen say that 

 when alive " the northern species is " very fat, and its sides round ; but the fat is so 

 liquid and oily that it runs from the body as soon as the fish dies. The Russians at 

 Archangel are said to purchase them for the fat they contain." Deal-fish is a name 

 applied to the Trachypterus arcticus in England, and Vaagmer in Iceland and other 

 northern countries. 



A remarkable development of the fins is manifested in very young fishes : the rays of 

 the anterior or nuchal portion of the fin are extraordinarily developed, and perhaps two 

 or three times longer than the body ; the ventrals are also long, and the caudal large. 



