THE REACTIONS AND RESISTANCE OF FISHES IN 

 THEIR NATURAL ENVIRONMENT TO SALTS 



MORRIS M. WELLS 



THREE FIGURES 



I. Introduction 244 



II. The water 244 



III. Methods and apparatus 245 



IV. Presentation of data 248 



A. Reaction experiments 248 



1. Reaction to chlorides 248 



a. Ammonium chloride 248 



b. Potassium chloride 248 



c. Sodium chloride 249 



d. Calcium chloride 249 



e. Magnesium chloride 250 



2. Reaction to nitrates 250 



. a. Ammonium nitrate 250 



b. Potassium nitrate ■. . . . 251 



c. Sodium nitrate ; 251 



d. Calcium nitrate 252 



e. Magnesium nitrate 252 



3. Reaction to sulphates 253 



a. Ammonium sulphate 253 



b. Potassium sulphate 253 



c. Sodium sulphate 253 



d. Calcium sulphate 254 



e. Magnesium sulphate 254 



4. Conclusions from reaction experiments 255 



B. Antagonising salts and the reaction of fishes 255 



C. Physiological states and the reactions of fishes 260 



1. Reaction of starved fishes to CaClo 262 



2. Reaction of starved fishes to low oxygen 264 



D. Acclimatization and the reaction of fishes 265 



E. Resistance of fishes to salts 267 



1. Resistance to ammonium salts 267 



2. Resistance to potassium salts 271 



3. Resistance to sodium salts 272 



4. Resistance to calcium and magnesium salts 273 



V. General discussion 274 



VI. General conclusions 280 



Bibliography 282 



243 



THE JOURNAL OF EXPERIMENTAL ZOOLOGY, VOL. 19, NO. 3 

 OCTOBER, 1915 



