PART III. SKELETAL DIMENSIONS. 



Skeletons were prepared of certain of the rabbits concerned in this 

 series of experiments, and upon these several series of measurements were 

 made. The most complete series are recorded in tables 29 and 30. 



In one case (cross i, table 3) the skeletons of both parents were pre- 

 served, as well as that of one of the fully-grown young, viz, 3 248. The 

 measurements of this animal (recorded in table 29) are approximately 

 intermediate between those of his respective parents. They include 7 

 different skull measurements and 7 of other parts, chiefly bones of the 

 appendages. 



The skull of the lop-eared rabbit is relatively much longer and more 

 slender than that of short-eared rabbits. (See plate 4.) The proportions 

 of half-blood lops (like their absolute dimensions) are intermediate, cor- 

 responding closely with the mid-parental or mean of the parents in this 

 respect. (See table 29, ratios.) 



The limb bones are shorter in proportion to the length of the innominate 

 bone in lop-eared than in short-eared rabbits. In this particular also 

 part-blood lops are intermediate. (See tables 29 and 30, ratios.) 



In the case of the rabbit c? 248, table 29, the deviation from the mid- 

 parental measurements or proportions in no case equals one-fifth of the 

 difference between the parents; in most instances it is much less. In this 

 animal the inheritance of skeletal dimensions and proportions is unmis- 

 takably blending. 



Measurements of another half-blood lop (9 167) are recorded in table 

 30. The mother's skeleton was not preserved. She was a short-eared 

 rabbit similar to c?45. If, then, the inheritance was blending also in the 

 case of 9 167, her measurements and proportions should resemble those 

 of c? 248, table 29. This, it will be observed, is the case. 



Measurements of a third half-blood lop (9 178) are recorded in table 

 30. The father of this rabbit also was the old male lop, table 30. The 

 mother was the Belgian hare (9431, table IA). In size and proportions 

 of parts the Belgian hare occupied an intermediate position between the 

 lop-eared and the small short-eared races used. Accordingly it is not 

 surprising to find that the half-blood daughter (9 178) deviates from the 

 other half-blood lops examined, both in absolute measurements and in 

 proportions of parts, being more like lop-eared rabbits than they are. 



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