934. 



ZOOLOGICAL SOCIETY BULLETIN. 



it is below them they must stand on their heads 

 to secure it. In the Aquarium they may be 

 even seen to turn partl\ r over backward to pick 

 food from the bottom. Mr. W. I. DeNyse, who 

 has observed them feeding in nature, informs 

 me that these positions are habitual with them. 

 The teeth of the filefish are very peculiar, but 

 well adapted to the function of cutting. In the 

 lower jaw there is a single series of sharp-edged 

 incisor-like teeth. These are opposed to a 

 double row of teeth in the upper jaw which are 

 so arranged that they present a single cutting 

 edge. The lower jaw closes inside of the upper 

 in such a way that an admirable pair of shears 

 is formed, and the trenchant function is further 

 increased by the serrated edge. 



The bones forming the bases of the fins are 

 very strong, especially the anterior ones of the 

 dorsal and anal series, which are remarkably 

 enlarged. The pelvic fins are entirely wanting, 

 but the pelvic girdle is modified to form a strong 

 brace consisting of a single bone extending 

 from between the jaws, where it is attached, the 

 full length of the abdomen, to which it lends 

 support and protection. The ribs are short and 

 very strong and are broadened posteriorly to 

 overlap, suggesting the uncinate processes of 

 the ribs of birds. 



In the Aquarium the tail is used almost en- 

 tirely as a rudder, and progress is made in an 

 awkward-appearing fashion by means of scull- 

 ing with the pectoral fins and by the undulatory 

 motion of the dorsal and anal fins. These move- 

 ments are reversed in swimming backward. 

 When rapid progress is desirable the tail is used 

 in the manner usual in fishes. 



While the orange filefish is known from the 

 Gulf of Mexico to Cape Cod, and even as far 

 north as Salem, Mass., it is naturally a fish of 

 the warmer seas and is found in this region 

 only during the warmer months. Whether they 

 migrate southward, or are killed by the cold at 

 the approach of winter, is not known. The 

 young, three inches and over, are fairly com- 

 mon along the coast of Long Island and south- 

 ern New England every summer, especially in 

 September, but the adults are more rare. A 

 few adults are usually taken each season at 

 Gravesend Bay and at Woods Hole, Mass., but 

 occasionally' several years will pass without the 

 capture of a single specimen. The present 

 season has been unusual in the appearance of 

 large numbers of adults at Gravesend Bay; as 

 many as seventy-five or eighty being taken at 

 a single haul of a pound net. 



The filefish reaches a maximum length of two 

 feet, but the largest taken in this region meas- 

 ured about eighteen inches. They present a 



rather bizarre appearance in the Aquarium, and 

 their peculiar and awkward movements seem 

 to have a greater attraction than usual for our 

 visitors. While the adults live fairly well, con- 

 siderable difficulty has been experienced in 

 handling the young, and it has not been possible 

 to keep them more than a few months. Probably 

 the difficulty lies with the character of the food, 

 although the diet has been varied as much as 

 possible in the attempt to rear them to maturity. 

 The filefishes have no economic importance 

 for the scanty flesh is bitter and offensive to the 

 taste, and it is not improbable that it is impreg- 

 nated with a poisonous alkaloid. Such poisons 

 are known to exist in the nearly related trigger- 

 fishes, some of which are so noxious as to cause a 

 severe disease, ciguatera, which not infrequently 

 results fatallv both to man and lower animals. 



COMMON SEA CATFISH 



AQUARIUM NOTES 



Tarpon. — A splendid mounted specimen of 

 the tarpon has been presented to the Aquarium 

 by Mr. H. Casimir de Rham, Member of the 

 Board of Managers of the New York Zoological 

 Society. The fish, which weighed one hundred 

 and sixty-five pounds, was taken by Mr. de 

 Rham with rod and line at Bahia Honda, 

 Florida. 



Aiding Investigators. — During the past year 

 the Aquarium has been able to aid biological re- 

 search in a number of ways. Owing to lack of 

 laboratory space and proper equipment but little 

 such work can be carried on within the walls of 

 the Aquarium building. Mr. George G. Scott 

 of the College of the City of New York, how- 

 ever, has pursued certain investigations on the 

 blood of fishes in an improvised laboratory. 



Dr. Jacques Loeb, of Rockefeller Institute, 

 has been supplied with large numbers of killie- 

 fishes for use in the investigation of certain 

 biological problems. Prof. C. F. W. McClure, 

 of Princeton University, has been furnished 

 with the eggs and embryos of salmonoid fishes 

 for the completion of studies on the origin and 

 development of the lymphatic vessels. 



