484 



CHARLES RUSSELL BARDEEN 



In table 8 are summarized the results of exposure of various 

 lots from three different batches. 'A' represents the 1909 batch 

 of specimens from which groups were exposed during all the pre- 

 ceding stages. *D' represents a 1908 batch, experiments on 

 which were described in the section immediately preceding this; 

 'F' represents a 1908 batch not previously described. 



TABLE 8 



Irradiation between hatching and metamorphosis 



A 



4} 



8 



55 m. 

 1 hr. 



100 

 100 



D 



LarvEB newly hatched at time of exposure. 

 Well developed tadpoles at time of exposure. 



Toad larvse after hatching but still disposed to lie on one side 

 in the dish are decidedly susceptible. After one and three- 

 quarter hours expostire in one lot 65 per cent of the specimens 

 died within a month after exposure (F-4|d); in a second lot 70 



