40 



ILUNOIS BIOLOGICAL MONOGRAPHS 



[160 



THE EFFICIENCY OF THE GOLDFISH AS A TEST ANIMAL 



In all substances tested the goldfish died fairly uniformly in any given 

 concentration where the survival time did not exceed five hours. See Tables 

 I to XXIV for data of experiments in which two goldfish were killed in each 

 solution tested. The variation of the survival time is better shown by data 

 of experiments given in Tables XXXI and XXXII in which a number of fish 

 were killed in each solution. The broken line in Figure 21 is a graphic repre- 

 sentation of the survival times of the 8 goldfish killed in 0.272 N. LiCl solu- 



TABLE XXXI 



The Variation in the Survtval Time of the Goldfish. 



Temperatttre 20° to 21° C. 



*Flsh was not dead when taken out of solution 



tion, Table XXXI. One block of abscissa represents an individual goldfish 

 and one block ordinate represents 100 minutes survival time of the goldfish in 

 the 0.272 N. LiCl. The goldfish with the shortest survival time is repre- 

 sented first and the second next and so on to the goldfish with the longest 

 survival time. Thus the deviation of the fine from the horizontal represents 

 the variation of the survival time of the goldfish in the given solution. Each 

 of the other lines of the graphs in Figures 21 and 22 represents the survival 

 times of individual goldfish in a definite concentration of a particular sub- 

 stance tested. In all graphs one block ordinate represents 100 minutes sur- 

 vival time and one block abscissa represents an individual goldfish. In these 



