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ZOOLOGICAL SOCIETY BULLETIN 



A NEW WAY 

 OF COLLECTING RARE FISHES. 



A most interesting collection of trop- 

 ical fishes has just been brought to the 

 laboratory of the Aquarium from the Tor- 

 tugas Islands, ofif Key West, Fla. The 

 specimens are remarkably well preserved, 

 and were collected during the past winter by 

 Dr. J. C. Thompson, of the United States 

 Navy, who has been attached to the Naval 

 Station located there. His studies have re- 

 sulted in adding about 150 species to the 

 number already known from that locality, 

 and there are several forms in the collection 

 new to science. 



The fish life of the Tortugas, lying on the 

 border of the Gulf Stream, is of a richness 

 probably surpassing that of any region 

 within the United States proper. The water 

 is of the characteristic tropical clearness 

 which enables the bottom to be seen plainly 

 through a water-glass to the depth of five or 

 six fathoms. 



The actual observation of marine life 

 among the sea-weed and in the crannies and 

 nooks of the coral reefs is a revelation to 

 one unacquainted with the conditions to be 

 found in such places. 



As no small part of the success in captur- 

 ing the rarities from the Tortugas was due to 

 a small electrical fishing appliance devised 

 by Dr. Thompson, he has been asked to pre- 

 pare the following account of his fish-catch- 

 ing experiments in those waters. 



It may be explained that the water-glass to 

 which he refers is simply a small box, or a 

 bucket, with a glass bottom. When the glass 

 is placed on the surface of the water fishes 

 and other objects can be seen perfectly. It is 

 used by pearl-divers, sponge-gatherers, and 

 by fishermen generally in tropical waters : 



"After spending several months collecting 

 in the Tortugas and employing the routine 

 methods for taking fish — the hook and line, 

 baited trap, seine, cast-net, and dynamite — 

 there still remained the records of many 

 fishes seen, but which had avoided capture, 

 and to these forms all possible attention was 

 given. One in particular, a magnificent 

 specimen of demoiselle, dark brown with 

 sapphire specks on back of head, and a bright 

 orange tail, lived for over three weeks in a 

 small cave under a coral ledge. This fish 

 could be approached to within a few feet, and 

 could with patience almost be touched with 

 the rim of a dip-net, but any sudden motion 

 would cause him to dash out of reach among 

 the rocks. These prohibited the use' of nets 



in any form, and no bait could tempt him, as 

 his appetite was appeased by nibbling some- 

 thing among the sea-weed that grew in 

 abundance. When watching this fish, atten- 

 tion was drawn more and more to the trait 

 that seems to be abnormally developed in 

 many fishes— curiosity. He would approach 

 and examine, apparently with no small in- 

 terest, one's limbs and shoes, while the net 

 and any bait that was dangled before him 

 he carefully scrutinized. To obtain this fish 

 it seemed necessary to devise a little piece oi 

 explosive bait, that could be controlled so as 

 to be fired at an instant when he was within 

 a few inches, and to so stun him that he could 

 be taken in a dip-net. 



"Such an apparatus can be used with per- 

 fect success when wading in shallow water 

 which is sufficiently clear to allow the fish to 

 be seen prior to capture. A small dry-cell 

 storage-battery was carried in a pouch 

 snugly fastened under the left arm. From 

 this led a couple of insulated wires, twisted 

 into a single strand about a yard long, and 

 connected by thumb-screws to two pillars of 

 a simple circuit-key, screwed into the side 

 of a water-glass near the rim, and in such a 

 position that it could be opened or closed 

 with one finger of the hand holding the glass. 

 Beyond the key was a two-ply strand of wa- 

 terproof insulated wire, about ten feet long, 

 terminating in a small fulminate cap, such as 

 is used to explode charges of dynamite. The 

 method of operating it is as follows : When 

 all electrical connections are made and the 

 key open, the wire is coiled and hitched 

 alongside of the water-glass, which is 

 floated on the surface of the water and 

 looked through as one wades cautiously 

 about. When the fisherman comes to a spot 

 such as experience alone will tell to be a 

 propitious one, and sees a desirable fish the 

 coil of wire is freed, and a couple of turns 

 taken about midway between key and bait 

 around the tip of the handle of a dip-net, 

 which thus reversed is used temporarily as 

 a fishing-pole. The bait is lowered slowly 

 into the water, and manoeuvred until it is 

 about a foot from the specimen, and the key 

 is then instantly closed. The resulting ex- 

 plosion will either kill or stun practically 

 every fish that may be encountered under 

 these circumstances. The wire is now slipped 

 from the net, which can be freely used. The 

 wire can be stored in the pouch for use later, 

 or a fresh cap can be attached and the pro- 

 cess repeated as long as the amnnmition 

 holds out. 



"Having the wire detachable from the key 

 on the water-glass enables one to stow the 



