70 



HELEN B. HUBBERT 



TABLE III 

 Group C— 200 Days 



1 case (**) or 4% uniformly progressive. 



2 cases (*) or 8% doubtful. 



21 cases or 88% not progressive. 



3 cases or 13% in which IV and V were eliminated before II and III. 



Here we find five rats eliminating IV and V before II and 

 III, or twenty-nine per cent. 



The averages show possible uniform progression, although the 

 values for III, IV and V are too nearly identical to warrant 

 such an interpretation. 



Group C— 24 Rats 



These rats began the problem when two hundred days old. 



Of them, one rat showed uniform progressive elimination, two 

 possible progressive elimination, while twenty-one did not show 



