52 BULLETIN 1121, U. S. DEPARTMENT OF AGRICULTURE. 
TABLE 18.—Average birth weight in grams of all young, born dead or alive. 
[Average in litters of each size and the index (litters of 1, 2, 3, and 4 weighted 1, 3, 3, and 1, respectively). 
Inbreeding and crossbreeding experiments, 1916-1919.] ; 
Size of litter. 
Experiment. SS pn ERS PS Index. 
1 2 3 4 5 6 7 
Oh Se Lee te eI et 86.0 72.0 60.1 50.5 AAG se eed 66.6 
TQ AUN Pee ee neog ies 101.9 80.8 68.4 59.2 50.7 BOG is eck 76.1 
SON cig SOME Te eG aa 98. 1 80. 0 66.4 57.4 SOP ok el ee ac Camis 74.3 
Se, A Me Dad lige Me 96.5 84.5 70.1 56.6 BOA ice cell oe eg 77.1 
2 ape en Bl ep ete Ao 85.8 72.6 63.0 50. 4 53.5 B7eRils ahwead 67.9 
Other. Ree ere 93.0 75.3 64.9 53.5 BG heen hal Se Oa 70.9 
Tnpred is No es ee 93.0 77.0 65.3 54.7 48.9 Ea eee 71.8 
rea tie Siler nua. rate 97.7 77.6 64.4 53.9 BR ea AUN 72.2 
UR Pasay NeEte STi ee Rar tO 107.0 86.0 72.5 63.3 BG 6 ber cae Oe wena 80.7 
TEs AC SE ee 100.3 95.8 75.7 65.9 60.3 4Gig 4. b eae 85.1 
CON coe wee 101.8 86.9 70.2 59.1 51.1 AOD see aR 79.0 
(et OR ula Geta MN. 104.2 84.4 69.8 63.5 BET Vee ee 2 78.8 
Oe CT ines TRE eee 104.5 84.8 72.9 61.0 Be ico eoal sais 79.8 
CI ae ig Ca MGs Wenn Wen 4 104. 5 90.8 78.3 66.0 56.5 BSG |e bb hed ta 84.7 
Ce Fae ee ee 106.7 87.5 79.0 62.8 59.2 54,0) [22 Sr sees 93.6 
Beas pee hy em oe | 101.2 86.9 71.8 61.7 57.0 54.7 24.5 79.9 
| 
TABLE 19.—Average birth weight, in grams, of young which were raised to weaning. 
{Average in litters of each size and the index oe pean Inbreeding and crossbreeding experiments, 
‘ . 1916-1919. 
Size of litter. 
Experiment. SS ee ee index. 
Caner rae ace 
=m OTR WOW ll MO OonyN 
PERERRGRN | SNEASE 
fe 
ior) 
