SEX RATIOS IN FCETAL CATTLE. 



TABLE I. 



263 



THE FCETUSES GROUPED ACCORDING TO LENGTH. The left-hand column gives 

 the group number in lots of 50. The lowest space gives the totals for the 

 i ndividuals of given lengths. 



to 50; next, from 50 to i oo; 100 to 150 and so on. In the column 

 to the extreme right is given the total for each space as a check 

 on the number of individuals, the total for all spaces being 1,000. 

 The group totals for different lengths, given in the lowest space, 

 show the males without exception to be more numerous than 

 the females, although in the 20-30 group the sexes approach 

 equality. In all, there are 552 males and 448 females, giving a 

 sex ratio of 123.21. If the sex ratio for each of these groups is 

 determined we get the following values (Table II.): 



It is obvious that in the o-io group and the 90-100 group the 

 number of individuals, 15 and 5 respectively, is too small to be 

 considered separately, especially since the sex ratio in each case 

 is so extremely high. In the 10-20 group the sex ratio of 136.5 is 

 well above the sex ratio of 123.21 for all individuals, while in 

 the 20-30 group it has fallen to 102.6. Then in the next four 

 groups from 30 cm. to 70 cm. the average sex ratio is 127.75. 



