NUMBERS OF YOUNG AND OF EGGS 343 



cows ranged from 240 to 321 days. Earl of Spencer reported 764 cows 

 with a range of 220 to 313 days. L. F. Allen reports results for one 

 year among a herd of 50 Shorthorns, Herefords, and Devons, as rang- 

 ing from 268 to 294 days, or an average of 284 days. Tessier observed 

 912 ewes with a range of 146 to 161 days. Darwin found that 

 Merinos run about 150 days, while Shropshires and Southdowns re- 

 quire only about 144 days. Swine vary from 109 to 123 days, but 

 usually run 116 days. 



In practice there are some causes which hasten birth. A sudden 

 cold spell will hasten the birth of a litter of pigs. Nervous excitement 

 will hasten birth, especially in cows. Parturition of a neighboring 

 cow often hastens birth. It is a popular opinion that male offspring 

 require a longer period of gestation. There is not sufficient evidence 

 to warrant this, but in one case of observation on cattle, the average 

 period for five years was males 288 days, females 283 days. Heredity 

 may influence the period somewhat. 



Number of young at birth (Harper) 



Elephant , 



Giraffe 



Buffalo 



Asa 



Mare 



Cow 



Bear 2 



Sheep 1-2-3 



Sow 2-14 



Beaver 4 



Lion 2 



Dog 3-8 



Cat 3-6 



Rabbit 4-8 



Squirrel 3-6 



Single-birthed animals occasionally bear twins. All multiple-birthed animals 

 are exceedingly variable in the number at a birth. 



[ Number of eggs in brood (Harper) 



Turkey 12-15 



Guinea-hen 15-18 



Pea-hen 10 



Ducks 9-12 



Geese 15-18 



Hen 12-15 



Pigeon 2 



Canary 3-4 



