360 



DISCOVERY REPORTS 



In Fin whales again the number of ventral grooves which occur seems to be purely 

 a matter of individual variation. Whale No. 67, for instance, had 72 grooves and its 

 foetus 96; No. 179 had 92 and the foetus 88; and No. 186 had 100 grooves and the 

 foetus 90. 



The numbers of grooves recorded and the variations which occur are shown in the 

 table at top of page 359. 



Here again there is no particular distinction between the sexes and localities. 



In development the ventral grooves have usually appeared by the time the foetus 

 reaches i m., and the full number is present at about 2-0 m. 



HAIR 



The positions at which the hairs are found have already been described in the 

 section on Blue whales. In Fig. 99 diagrams are shown of the arrangement of the 

 hairs on the chin of eight Fin whales and the rostrum of one. The arrangement on the 

 chin in Nos. 137 and 169 is very typical of Fin whales. 



The hairs on the chin occur in about the same numbers as on Blue whales. The 

 following is an analysis of the records made : 



Thus the figures for males and females correspond very closely and the few readings 

 from South Africa fall close to the averages for South Georgia. 



FOOD, BLUBBER, AND EXTERNAL PARASITES 



It will be convenient to consider the food of whales together with the blubber and 

 parasites in this section. The three subjects are not so disconnected as they first appear 

 to be, for variations in the condition of the blubber are directly dependent on the 

 whale's feeding, and the study of certain parasites involves investigations into the 

 structure, and normal and pathological conditions of the blubber. 



