CLASS V. PISCES: ORDER 3. TELEOSTEA. 445 



Genus NAITCRATES : Naucrates. — This includes the Pilot-Fish, N. ductor, noted for its 



habit of accompanying ships for weeks 

 «j§§vifi^^^^^^^!^^^^7™»s5», together; the ancients even asserted 



that it pointed out the proper course to 

 the mariner when lie was at a loss how 

 to proceed, leaving him when he had 

 arrived in sight of the desired haven. 

 It appears probable, however, that the 

 Pilot-Fish only attends the voyajrer for 



THE PILOT-FISH. l /» l . p p 



the sake of the numerous pieces of food 

 whicli arc constantly being thrown overboard ; and a community of feeling in this respect may 

 perhaps account for the frequent association of the Pilot-Fish and the Shark. It is, however, a 

 general opinion among navigators that the Pilot-Fish really attends upon the Shark as a guide ; 

 and an instance has been related in which two of them led a shark to a baited hook that had been 

 thrown out for him. Another observer, however, states that he saw a shark, which was inclined 

 to swallow a bait put out for him, prevented from doing so by one after another of four Pilot- 

 Fishes which accompanied him ; and that when at length the shark had swallowed the tempting 

 morsel and was being hauled out of the water, one of his diminutive friends clung to his side for 

 some little time. Colonel Hamilton Smith also states that he had witnessed a similar circum- 

 stance. The Pilot-Fish attains a length of about a foot. It is somewhat of the mackerel form, 

 of a silvery-gray color, bluish on the back, and adorned with five dark blue bands, which go 

 round the whole body. Its flesh is said to be very good. It is extensively distributed through- 

 out the Atlantic, and is said to be occasionally seen on our coasts. 



The New York Pilot-Fish, iV. JVoveboracensis, resembles the preceding, and may be of the 



same species. 



THE XIPHIIDJE. 



This family includes several species called Sword-Fishes. 



Genus XIPIIIAS: Xiphias.— ThismcladGsthc Common 8vf orb-Fish, X. r/ladius ; it is twelve 

 to twenty feet long, and has the upper jaw prolonged into a long, bony, spear-like weapon. It 

 is most predaceous in its habits, employing its spear for the destruction of the larger fishes. It 

 is even said to attack whales. Its activity and strength are very great ; and it has been known 

 to strike at ships passing through the water, and to bury its weapon in their timbers. Cuvier 

 states that a parasitic crustacean buries itself in the flesh of the sword-fish, and torments it to 

 such a degree that it will sometimes rush upon the shore; the same cause of irritation may 

 perhaps have something to do with its suicidal attacks upon such a very unequal antagonist as a 

 ship. This species is found in European and North American waters ; the seas of tropical climates 

 contain several others. Their fiesh is said to be exceedingly good, especially when young. 



THE CORYPH^NID^. 



This includes, among other species, the Dorado, CortjphcBna hippurus, sometimes called 

 Dolphin, noted for its beautiful metallic tints, the swiftness of its course, and for the per- 

 petual war of destruction which it wages against the flying-fish. It is about five feet long, the 

 back bluish, the body yellow, the whole spotted with darker hues. When in the water it pre- 

 sents a splendid golden luster, which rapidly vanishes when taken out of its natural element. 

 This fish is common in the tropical seas of the Atlantic. 



The Bottle-headed Dolphin, C. glohiceps, resembles the preceding, and has been taken on 



our coasts. 



THE NOTACANTHID^. 



This family includes several species of fishes which have an elongated, eel -like form, the liinder 

 extremity being usually surrounded by the same continuous fin that is characteristic of the eels. 

 The whole surface is covered with small cycloid scales. Most of the species inhabit the tropical 

 regions, some living in salt and some in fresh water. One species, the JVotacanthus nasus, is 

 found in the Arctic Ocean. 



