EAR-SIZE 



11 



spread of the ears, i. e., the distance from ear- tip to ear-tip when the ears 

 are extended in a horizontal position and stretched slightly. Since the 

 measurements in nearly all cases were made by the same observer (Walter), 

 the personal equation is a fairly constant factor and may be disregarded 



Ear length 



in 777777. / 2 3 4 5 6 7 8 9 10 II / /3 14 /5 16 17 Id 19 

 IZO 



//O 



90 J 



70- 



60- 



50 



30 



weigl 

 in 

 grarr 



'1500 

 1400 



1300 



-1200 

 1100 

 1000 

 900 



-800 

 700 

 600 

 600 

 400 

 300 

 200 

 100 



A 9 em I 2 3 4 5 6 7 8 9 10 II IZ 13 /4 15 16 17 /8 /9 



weeks. 



FIG. i. Chart showing growth in ear-length, and body-weight of a litter of six short-eared 

 rabbits between the ages of two and eighteen weeks. See table i. 



