THE SPERM WHALE 



137 



7 months but is mainly concentrated into 5 months. The two isolated points on the left 

 of Fig. 39 now fall into position on the right in this diagram ; in other words, in Fig. 39 

 the central group of points represents the current season, the left-hand group represents 



in 



jU 4. 



OJ 



E 



3- 



c 



QJ 



OJ 



Aug 5ep Oct Nov Dec Jan Feb Mar Apr Maij Jun Jul Aug Sep Oct Nov Dec Jan Feb 

 Fig. 40. Sperm whale. Average foetal lengths by months. 



Last Season 



Current 



Deason 



Next Season 



Apr Mai) Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar 

 Fig. 41. Sperm whale. Foetal lengths by months, and breeding seasons. 



late breeders of the last season and the right-hand group represents the beginning of 

 the next season. 



If in Fig. 41 lines are drawn parallel to the average line, but taking their origin at 



