26 



Scientific Proceedings (6i). 



rabbits and fowls. The lead acetate was mixed with sugar of 

 milk and fed in gelatin capsules. 



A. Rabbits. 



Two series of experiments were run. In the first (I) a normal 

 homozygous Dutch-marked male (cf 20.2) and a poisoned albino 

 male (cf 26.8) were both bred to a number of albino females. 

 In the other series (II) an albino male (cf 21.4) was used as the 

 normal or control animal, while the previous control male (Dutch 

 cf 20.2) was subjected to the lead treatment. The results from 

 the two series are shown in Table I. 



A comparison of the two series shows: (1) The mortality of 

 the albino young within four days after birth dropped from 47.7 

 per cent, when the albino male (cf 26.8) was poisoned to 29.2 per 

 cent, in those young which came from the normal albino male 

 (cf 21.4). (2) The mortality of the pigmented young in the same 

 period rose from 18.9 per cent, in Series I, when the pigmented 

 male (cf 20.2) was normal, to 34.2 per cent, in Series II, after 

 he had received the lead treatment. (3) Coincident with the 

 lower death-rate in the albinos in Series II over those in Series I, 

 it will be noticed that there is a distinct rise in the average weight 

 of the young at birth — from an average weight of 49.8 grams when 

 the father was poisoned to 59.0 grams when the father was normal. 

 (4) The average weight of the young of the pigmented male 

 before he was given the lead was 54.7 grams; after the treatment 

 the average weight of the young produced dropped to 49.1 grams. 

 In this connection it should be mentioned that both albino males 

 were considerably larger than the Dutch (cf 20.2), the former 

 varying around about 2,900 grams, while the latter averaged 

 only about 2,100 grams. In spite of this his offspring averaged 

 larger than those of the poisoned albino male. 



From the foregoing it seems legitimate to conclude that the 

 offspring produced by male rabbits which have been poisoned by 

 the ingestion of lead acetate into the alimentary tract have a lower 

 vitality and are distinctly smaller in average size than normal 

 offspring of unpoisoned males. 



