16 



INHERITANCE IN RABBITS 



Another mating which falls in this category was made between the 

 Belgian hare (9 431) and the short-eared d 1 56 (see table IA). It shows 

 a complete blending in the offspring of the parental ear-lengths, with a 

 very small range of variation, viz, 6 mm. 



TABLE IA. 



The mid-parental ear-length was exceeded by i of the young at 21 

 weeks of age; 3 others came within 2 mm. of the mid-parental ear-length 

 at 21 weeks of age, and i of these equaled it when adult. If the other 2 

 did as well they too must have attained the expected ear-length. Only 

 i individual (9232), then, fails to attain the mid-parental ear-length. 

 This result is almost identical in general character with that shown by 

 table i. 



We may conclude that short-eared rabbits breed true within a range of 

 fluctuating variability not exceeding 10 mm. 



MATINGS OF LOP-EARED RABBITS INTER SE. 



Our original stock of lop-eared rabbits consisted of a single pair. Both 

 of them gave vigorous young in matings with short-eared rabbits, but not 

 with each other. Consanguinity may have been the reason for this lat- 

 ter fact. They were obtained from the same source, and doubtless were 

 nearly related, as well as inbred. Nevertheless we did obtain from them 

 two good-sized and healthy young, J 179 and 9 180. The former appears 

 in many of the crosses to be described, but the latter proved a very poor 

 mother, producing only occasional litters of young, none of which attained 

 maturity. Table 2 shows the only results obtained from mating lop-eared 

 individuals inter se. 



Mating i produced 2 young, one (d 1 179) very similar to the father, the 

 other (9 180) very similar to the mother, but not quite so large and with 

 ears 5 mm. shorter. The deviations from the mid-parental ear-length 

 are 7.5 and 2.5 mm., respectively. 



