THE EFFECT OF ETHER ' AND CHLOROFORM ON 



CERTAIN FISHES. 1 



HAROLD D. CLAYBERG. 



PAGE. 



I. Introduction 234 



II. Reactions 235 



1. Material and Methods 235 



2. Reactions and Standardization 236 



3. Chloroform 238 



4. Ether 238 



III. Resistance 239 



IV. Comparison of Ether and Chloroform Killing Curves 243 



V. Poisoning Symptoms 245 



VI. Summary of Conclusions 247 



VII. Bibliography 247 



I. INTRODUCTION. 



Various drugs which cannot be standardized chemically must 

 be standardized biologically before being used for medical 

 purposes. The time required to kill an animal (for example, a 

 goldfish) has been used for this purpose (see particularly Pit- 

 tenger and Vanderkleed, 1915). The discussion about digitalis 

 has been particularly keen. The effect of a large series of coal 

 tar derivatives upon various wild fish has been studied by Shel- 

 ford ('17) in connection with stream pollution work. He deter- 

 mined their relative toxicity by killing specimens of the orange- 

 spotted sunfish. The work described below was undertaken 

 with the two common drugs, ether and chloroform. Their 

 effect on the orange-spotted sunfish and on certain other wild 

 species was studied in the hope that it might serve -to relate the 

 coal tar results with those of the investigators interested in the 

 standardization of drugs with domestic goldfish. 



It is the purpose of this paper to point out that there seem 

 to be three possible ways of standardizing a drug with fish. 



i. Type of behavior in a gradient between pure water and 

 water plus the drug being tested might be used. To furnish 



1 Contribution from the Zoological Laboratories, University of Illinois, No. 90 



234 



