TABLES. 



123 



Table G8. 



Coefficients of variahilily of sixteen different skeletal dimejisions of the females in the 

 guinea-pigs and hybrids. 



Table 69. 



A verages of the coefficients of variability of sixteen measurements in the hybrids 

 and guinea-pig * 



*The probable errors were calculated from the formula: 



Cica — 



-n\ 



e, + e., + e. + 



accordin,^ to which the probable error of the average of a series of statis- 

 tical determinations is equal to the reciprocal of the number of determi- 

 nations into the square root of the sum of the squared errors of the 

 individual determinations. 



Table 70. 

 Occurrence of an interparietal bone. 



