424 



ZOOLOGICAL SOCIETY BULLETIN. 



in the office of the Aquarium. Tlie last, how- 

 ever, is merely the elongated canine tooth of 

 a small whale, (Monodon monoceros), inhab- 

 iting Polar seas, and cannot be classed as a 

 fish's weapon like the other two shown in the 

 picture. In fact, it is not definitely known 

 that the narwhal's tusk is a weapon at all. 

 The tusk (sometimes there are two) is de- 

 veloped only in the male and has been known 

 to grow to a length of nine feet four inches. 



The sword, however, is a weapon, and one 

 to be reckoned with, when attached to the 

 head of an angry swordfish, ( Xipliias glad- 

 ius). The fish does not hesitate to charge 

 the hull of a vessel. In the Academy of Sci- 

 ences in Philadelphia there is a piece of four- 

 inch planking through which a swordfish- 

 sword has been driven with terrific force, the 

 weapon remaining in tlie wood A\here it had 

 broken off. 



The swordfish attains a weight of 600 

 pounds, and the sword a length of nearly six 

 feet. The real use of the sword to the fish 

 is not in inflicting injui'ies on its enemies, but 

 in obtaining its food. It is the habit of the 

 monster fish to charge schools of mackerel 

 and other fishes and disable many of them by 

 violent thrashing of the sword from side to 

 side. 



The saw of the sawfish, (Pristis pectina- 

 tus), is used in precisely the same manner, 

 fishes in schools being impaled or disabled b}' 

 the sharp spines on each side of the saw. 

 The saw sometimes exceeds six feet in length, 

 and the whole fish has been found nearty 

 twent}' feet in length. Other fishes bearing 

 swoi'ds, but of smaller size, are the spear-fish, 

 (Tetrapterus hnperator), and sailfish, (Is- 

 tiophorus nigricans). In all these fishes the 

 weapon is a flattened beak-like prolongation 

 of the bones of the skull. 



A number of fishes possess weapons which 

 make them dangerous to handle. The lan- 

 cets on each side of the tail of the surgeon- 

 fish (Teuihis), usually to be seen in the 

 Aquarium, inflict serious cuts. They lie in 

 shallow grooves and are erected instantly 

 when the fish is angry or alarmed. 



The sting of the stingray, (Dasyatis), is 

 a serrated bony weapon situated on the tail, 

 and very effective when thrust forward. It 

 strikes with force and inflicts an ugly wound. 



Very many fishes possess dangerous spines 



which are defensive rather than offensive. 

 Among these may be mentioned the spines of 

 catfishes, sculpins, rockfishes and sticklebacks. 

 The remarkable "paddle" of the paddle- 

 fish, ( Foli/odon spathula), of the Mississippi, 

 although nearly one-third the length of the 

 fish, is in no sense a weapon, being chiefly an 

 organ of touch with which it stirs the mud in 

 search of its food. The greatest recorded 

 weight of the "paddlefish" is 163 pounds. 



ELECTRICAL FISHES. 



THE celebrated electric eel, (Electro- 

 phorus cJcctricus), of South America — ■ 

 the most powerful of electric fishes, is 

 not the only species capable of producing an 

 electric shock. Although not so large, the 

 electrical rays or torpedoes of our own At- 

 lantic and Pacific coasts are able to discharge 

 quite forceable electrical shocks. 



The electric ray resembles in size and gen- 

 eral appearance the familiar sting-ray, but 

 has a more rounded snout. It is found along 

 the Atlantic coast from Massachusetts soutii- 

 ward. Specimens taken at Woods Hole, 

 Mass., have been offered to the Aquarium, but 

 unfortunately have not lived long enough to 

 be transferred. The I\Icditerranean species 

 is sometimes exhibited at the Naples Aquar- 

 ium. The writer has experimented with the 

 electric ray in the Naples Aquarium suffi- 

 ciently to appreciate the force of the shock 

 it can give. The European species is said to 

 attain a weight of 200 pounds. Electric 

 rays or torpedoes, (Tetronarce), are found 

 in nearly all warm seas. 



The electric eel of the Amazon and Ori- 

 noco waters attains a length of over six feet. 

 Its electrical organs are two masses of tissue 

 extending along the tail, which, in this fish 

 comprises the greater part of the animal. 

 When its battery is put into action, it is said 

 to be severe enough to knock down domestic 

 animals in shallow water. 



Since this fish is known to endure trans- 

 portation, an effort will be made to procure 

 specimens for the Aquarium. Specimens 

 sent to London in 1842, lived sevei'al years in 

 captivity, and attained weights of forty and 

 fifty pounds. 



The electric catfish, (Torpedo clectricus), 

 of the Nile and tropical Africa, is a fish at- 



