242 DISCOVERY REPORTS 



3182 many were probably present in the epididymis. None of these whales, therefore, 

 seem to be definitely inactive. 



The testis appears to be active in some whales at all times of the year, or at least in 

 the months of February, March, April, July, August and September, and indications 

 of a seasonal sexual cycle must be sought for rather in the female than in this sex. 



Table XVIII. Sei whale. Males. Histological activity of testis and epididymis 



THE FEMALE 



External genitalia. In form and arrangement the external genitalia of the female Sei 



whale are very similar to those of the Fin whale. The vulva is a median groove placed 



at an average distance of 27 per cent of the body length in front of the anus. A vaginal 



band is present occasionally. Sixty-two whales were examined for this structure ; a band 



