746 



ZOOLOGICAL SOCIETY BULLETIN. 



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COMMON SKATE. 

 Upper side. 



In tile young fi.sliis, beforu tlu^y descend to the 

 bottom, the eyes are symmetrically placed, one 

 on either side of the head. If they were to re- 

 main in this position, one of the eyes would be 

 directed downward against the bottom and would 

 be entirely useless. During the metamorphosis, 

 however, tlie eye of the lower side sliifts its |30- 

 sition till it appears on the other side of the 

 head. This is brought about in two different 

 ways, according to the species. In those species 

 in which the dorsal fin does not extend forward 

 on top of the head, the eye shifts around the top 

 of the head till it comes into the final position, 

 but in those species which have the dorsal fin ex- 

 tended upon the head, the eye actually migrates 

 through the tissues of the head between the fin 

 and the frontal bone to get into its functional 

 position. This is one of the most remarkable 

 phenomena in the life history of anv fish, but 

 its adaptive significance is un(]uesti()nabk-. 



In swimming slowly the dorsal and anal fins, 

 which are developed to such an extent that they 

 nearly surround the body, move in a wave-like 

 motion similar to that of the lateral paired fins 

 of the skate. In more rapid swimming the 

 whole bodj^ is undulated as in other fishes, but 

 because of the position of the body the undula- 

 tions are vertical instead of horizontal. 



Manjf of the flounders have the peculiar habit 

 of burying themselves in the sand with the prom- 



inent eyes protruding above the surface. In 

 size, they range from small s]iecies a few inches 

 in length to the huge halibuts which attain a 

 lengtli of eight feet and a weight of .'500 pounds. 

 The eggs of this group are small and float at 

 the surface, and it has been estimated that the 

 halibut produces 3.500,000 eggs at one time. 



R. C. O. 



AQUARIUM NOTES. 



CoiitrUiittions : — During the past year the 

 New York Zoological Society has acquired by 

 ))U)cli.ise for exhibition at the Aquarium, 411' 

 spteinu IIS of tropical life from the Bermudas, in 

 fi\e shipuu iits, and 192 local fishes from the 

 steamer Angler. The Zoological Society has 

 received in gifts for use at the Aquarium, one 

 pair of Alaska fur-seal pups and 3.820,000 

 trout and salmon spawn from the United States 

 Bureau of Fisheries, besides 397 sjiecimens from 

 seventy-six private donors. In addition to this 

 we have exchanged for ninety-seven and bought 

 twelve specimens. Eleven seining trips were 

 made to the various parks of the City with the 

 result that 3,303 specimens for exhibition and 

 food were obtained. Our oflicial collector, Mr. 

 John .1. DeNyse, collected 50.5 fish, 4,185 in- 

 vertebrates and 750,000 spawn for exhibits, be- 

 sides much material for scientific work. We 

 have had twelve contributors to the library. 



