A METHOD OF STUDYING THE LIFE HISTORY OF FISHES. 



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By CHARLES F. HOLDER. 



The owners of the island of Santa CataUna, Cal., latitude 33°, at my sugges- 

 tion established a small zoological station, which was thrown open free to stu- 

 dents who would come with letters from teachers. The aquarium cost about 

 $10,000. The tanks were placed out in the room so that they could be exam- 

 ined from all sides and the light reach all parts. For all purposes this plan is 

 the most satisfactory, though it does lose the glamor of the "dark, unfathomed 

 caves," which, as often seen in aquariums, are unnatural. Nearly all fishes 

 that live near the surface like the sunlight as it sifts down through the water, so 

 in the zoological station the tanks are bright and clear, and the fishes can be 

 seen, slightly magnified, from all sides, and studied or admired. 



No better opportunity to study the life history of fishes can be imagined, 

 and as the fauna resembles that of the Bay of Naples, or, if possible, is richer, 

 the field is an interesting one and almost totally missed by zoologists who take 

 tables at Naples, paying for them, when they could have a greater opportunity 

 here for nothing. Through the courtesy of the owners I have had the entree to 

 this aquarium and have made many interesting observations. 



In observing the habits of fishes I have taken, for example, the shiner, a 

 surf fish, keeping it before me constantly. During the breeding season I 

 observed the birth, which was tail first, of the remarkably large young, and had 

 them before me until they reached the adult stage. The development of the 

 Garibaldi was more interesting, as it is at first a beautiful metallic blue, iri- 

 descent, and gradually, as it grows, assumes an orange-red tint, until when 

 nearly 2 years old it is almost entirely orange. I watched the changes, kept 

 the fish in different tanks, and tried them with different foods and colors. I 

 had a tank built about 3 feet long, 8 inches wide, and 2 feet high, which I used 

 in photographing fishes at different ages and stages of their development. The 

 tank could be arranged with the weed in which the fish live in a state of nature, 

 and was placed on the roof of the aquarium in the sun. It was so narrow that 

 the prisoners could not get away from the camera, hence were easily photo- 



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