oe 
cow is consequently 0.045 higher in 
butter-fat percentage than her dam and 
0.508 per cent higher than her sire. 
The top graph in Figure 25 represents 
the butter-fat percentage of Crossbred 
No. 22, her Guernsey dam, College 
Creusa and her Aberdeen-Angus sire, 
Kayan. As explained in the previous 
paper, the graphs in Figure 25 are less 
reliable than those of Figure 24, since 
they are composed of a less number of 
lactations for the crossbred cows. 
Little difference in the butter-fat per- 
centages of these three animals are 
shown by the graphs. The eight 
months butter-fat percentage of Cross- 
bred No. 22 was 4.526, the butter-fat 
percentage of her Guernsey dam 4.825 
and of her Aberdeen-Angus sire 4.386. 
Crossbred No. 22 is 0.299 per cent of 
butter-fat less than her dam and 0.140 
per cent more than her sire. 
The butter-fat percentages of Cross- 
bred No. 26 and her parents, Creusa of 
Orono 3d, Guernsey dam, and Kayan, 
Aberdeen-Angus sire, are shown in the 
second graph in Figure 25. Little dif- 
ference in the monthly butter-fat per- 
centage of the three animals is seen in 
the graphs. The mean eight months 
butter-fat percentage of Crossbred No. 
26 is 4.100, that for the Guernsey dam 
4.679 and for the Aberdeen-Angus sire 
4.386. Crossbred No. 26 has 0.579 per 
cent of butter-fat less than her dam and 
0.286 per cent less than her sire’s po- 
tential butter-fat percentage. 
The butter-fat percentage of Cross- 
bred No. 27 is seen to vary irregularly 
over that of her two parents in the 
third graph of: Figure 25. Crossbred 
No. 27 is the result of a cross between 
Orono Madge, Aberdeen-Angus cow, 
and Lakeland’s Poet, Jersey bull. The 
average butter-fat percentage of Cross- 
bred No. 27 is 4.474, of her Aberdeen- 
Angus dam’s 4.640, and of her Jersey 
sire 4.705. Crossbred No. 27 was 0.166 
per cent of butter-fat less than her dam 
and 0.231 per cent of butter-fat less 
than her sire. 
While Crossbred No. 29 is the result 
of a cross between Creusa’s Lady, 
Guernsey dam and Kayan, Aberdeen- 
Angus sire, she is of some interest, since 
The Journal of Heredity 
her dam, Creusa’s Lady, is one of the 
higher butter-fat testing Guernsey 
cows. The fourth graph in Figure 25 
shows the monthly butter-fat percent- 
age for this mating. For the first 
month the butter-fat percentage of the 
crossbred is higher than that of either 
parent. After this time her butter-fat 
percentage follows the butter-fat per- 
centage of the relatively lower testing 
Aberdeen-Angus parent. The mean 
butter-fat percentage for the eight 
months period is 4.534 per cent for the 
crossbred cow, 5.346 for her pure bred 
dam and 4.386 per cent for her sire. 
The crossbred is 0.812 per cent less in 
her butter-fat test than her dam and 
0.148 per cent more than her sire. The 
crossbred cow resembles her low test- 
ing parent 5.5 times as closely as she 
does her high testing parent. 
The average butter-fat percentage 
of the Ayrshire breed is 3.68 per cent. 
This is about 1.0 per cent below the 
butter-fat percentage of the Aberdeen- 
Angus contained in this herd, and only 
0.4 per cent above the average of the 
Holstein-Friesian breed. | Crossbred 
No. 37 is the result of a cross between 
the Ayrshire cow, Dot Alaska and the 
Aberdeen-Angus sire, Kayan. The 
fifth graph of Figure 25 gives the butter- 
fat percentage of Crossbred No. 37 and 
her parents. The crossbred’s record is 
for only one complete lactation and one 
half of the next. Considerable varia- 
tion would consequently be expected 
for this record. In the fifth month of 
lactation the butter-fat percentage of 
Crossbred No. 37 is slightly higher than 
that for the high testing parent, Kayan. 
Other than this record the butter-fat 
percentage of the crossbred closely ap- 
proximates that for the lower testing 
parent, Dot Alaska. The eight months 
butter-fat percentage for Crossbred 
No. 37 was 3.861 per cent, for Dot 
Alaska was 3.661 per cent and for Kayan 
4.386 per cent. Crossbred No. 37 is 
0.200 per cent more in her butter-fat 
percentage than that of her dam, and 
0.525 per cent less than her Aberdeen- 
Angus sire or the ratio is 1 to 2.6. 
The last graph in Figure 25 is that for 
Crossbred No. 44. Crossbred No. 44 
