THE ACTION OF VARIOUS PHARMACOLOGICAL AND 



OTHER CHEMICAL AGENTS ON THE CHROMA- 



TOPHORES OF THE BROOK TROUT SAL- 



VELINUS FONTINALIS MITCHILL 



JOHN N. LOWE 

 From the Department of Zoology, University of Wisconsin 



THREE TEXT FIGURES AND ONE PLATE 



CONTENTS 



Material and methods 14g 



Reactions to gases 150 



1. Oxygen 150 



2. Carbon dioxide 150 



Effect of distilled water 151 



Reactions to salts 152 



1. Effects of potassium salts 153 



2. Effects of sodium salts 154 



3. Discussion 156 



Reactions to alcohols 163 



1 . Methyl alcohol 164 



2. Ethyl alcohol 164 



3. Propyl alcohol 167 



Reactions to alkaloids i69 



1. Strychnine 170 



2. Picrotoxin 172 



3. Morphine I73 



4. Caffeine I74 



5. Curara 176 



6. Nicotine 178 



7. Atropine 179 



8. Cocaine 180 



9. Veratrine 181 



10. Quinine 182 



Summary I83 



Bibliography 187 



The reactions of melanophores (pigment cells) to pharmaco- 

 logically active agents have been but little investigated. In the 



147 



