28 4 



ELLINOR HELENE BEHRE. 



A. Long Time Acclimations. 



In the first series of experiments, stocks of worms were used 

 which had been in the three temperatures for periods of time 

 from three days .to three months. The susceptibility of lots of 

 worms from each of these stocks was then tested at a different 



temperature and compared with that of worms which had been 

 living at that temperature. All possible combinations of tem- 

 peratures were used. The graphs represented by Figs. I and 2, 

 from worms with one week "acclimation," with temperature 



ordinates these values multiplied bv the number of worms in each stage at each 

 time interval, with the time intervals as abscissae. 



Since ten worms were used in each series, the highest possible numerical total, 

 i. e., the largest ordinate, will be 40, and will be attained when all the worms have 

 reached Stage V., i. e., are dead and disintegrated. The axis of ordinates is therefore 

 divided into 40 spaces, each representing one unit of numerical value, and since the 

 progress of death is most easily represented by descending curves, the ordinates are 

 measured from above downward. Thus, for example, if we have a lot of ten 

 worms which at a given time show the following groupings as regards stages of 

 disintegration : 



Stage I. Stage II. Stage III. Stage IV. Stage V 

 2 worms 2 worms 4 worms 2 worms 



The sum of the numerical values will be 2 +4 + 12 -1-8 = 26, which is the ordi- 

 nate for the curve at this time, and is to be measured downward from the zero 

 point (see Fig. i). 



