THE REPRODUCTIVE ORGANS 397 



THE UTERUS 

 The Uterus consists of a relatively short corpus and two long cornua which are 

 generally to be found close to the ventral wall of the abdominal cavity. There 

 is no particular feature of its gross anatomy which needs any special consideration 

 but an account of its growth in the young whales and the alterations in size which it 

 undergoes at different stages may be given. The routine observations which have 

 been made on the uterus consist in the measurement of the width of one cornu 



25- 



20- 



UJ15- 



Z 



w 

 u 



D 

 X, 



• «• o 



I I I I 1 I I I ~~i I 



18 19 20 21 22 23 24 25 26 27 



LENGTH OF WHALE IN METRES 



Fig. 131. Blue whales. Size of uterus in whales of different classes and different sizes. 

 . Immature. • Resting, o Recently ovulated. ® With very small foetus. x Lactating. 



as it lies in the collapsed condition on the flensing platform, and records of any con- 

 gestion observed when it has been slit open. Histological examination has also been 

 undertaken in many cases. 



During the period between birth and sexual maturity the uterus undergoes no 

 important change other than a gradual increase in size to keep pace with the growth 

 of the body. The sizes of the uterus in immature whales of various lengths is shown 

 in Figs. 131 and 132 and it is seen that it does not much exceed 8 cm. in Blue whales 

 measuring less than 22-0 m., or 7 cm. in Fin whales measuring less than 19-0 m. 



