THE HUMPBACK WHALE Si 



information allows some tentative conclusions to be drawn. The results of an examination 

 of these testes are summarized as follows : 



No. 408. Length 13-0 m. 22. i. 26. South Georgia. Testis volume 3330 c.c. Adult. The material 

 appears to have undergone post-mortem changes. The interstitial tissue appears to be swollen and the 

 tubules distorted. The tubules are loosely filled with cells and a few of them are clear of cells towards 

 the centre. No sign of activity is apparent in the cells and no spermatozoa are to be found. 



No. 3205. Length 14-5 m. 11. iii. 30. South Georgia. Testis volume 12,500 c.c. Weight 9-5 kg. 

 Adult. Testes not active. The lumen of nearly all the tubules is clear, but a few are loosely packed 

 with cells. No spermatozoa or dividing cells. 



No. 94. Length 8-4 m. 16. iii. 25. South Georgia. Testis volume 395 c.c. Immature. The tubules 

 lined with a layer of small cells and filled with large cells. No spermatozoa or signs of activity. 



No. D. 99. Length 11-9 m. 24. vii. 30. Durban. Testis volume 6100 c.c. Weight 4 kg. Adult. 

 Smear from the testis showed very few spermatozoa and that from the epididymis contained none. 

 The epididymis contained a thick fluid filled with epithelial cells. 



No. D. 129. Length 13-15 m. 6. viii. 30. Durban. Testis volume 10,100 c.c. Adult. Asmearfrom 

 the testis showed a few spermatozoa and that from the epididymis showed a fair number. 



No. D. 130. Length 1275 m. 6. viii. 30. Durban. Testis volume 16,400 c.c, weight 8-5 kg. 

 Adult. The smear from the testis showed a few spermatozoa and that from the epididymis showed 

 very few. 



No. 2768. Length 14-07 m. 15. xii. 29. South Georgia. Testis volume 11,700 c.c, weight 8 kg. 

 Adult. The lumen of nearly all the tubules quite clear and a single row of cells lining the wall. A very 

 few tubules contained loosely packed cells, some of which are in early stages of division, but no 

 spermatozoa. No spermatozoa found in the epididymis. 



No. 2848. Length 12-27 m. 26. xii. 29. South Georgia. Testis volume 11,300 c.c. Adult. No 

 spermatozoa present in smears from testis or epididymis. 



No. 2042. Length 983 m. 28. xii. 28. South Georgia. Testis volume 600 c.c. Immature. Tubules 

 lined with small cells and lumina filled with large cells. No activity. 



Of the nine male Humpbacks detailed above two are immature ; of the adults one was 

 killed in January, one in March and two in December at South Georgia; and one in 

 July, and two in August at Durban, South Africa, 



No spermatozoa or signs of activity of the testes were found in any of the South 

 Georgia whales, but spermatozoa were present in all those from Durban, though not 

 plentifully. It would appear, then, that the time of the male sexual season lies, probably, 

 between March and December. 



THE FEMALE 



External genitalia. The reproductive aperture of the female Humpback is situated 

 at a distance of about 4-0 per cent of the body length from the anus. It is tightly closed, 

 though patent, in immature females, but data from mature females are too scanty to 

 correlate its condition in them with the stages of the reproductive cycle. 



On two occasions remains of a vaginal band crossing the entrance of the vagina were 

 found. In neither of these was the band complete, but was represented by a tag attached 

 anteriorly. Both of these whales were mature, one pregnant, the other lactating. Thirty- 

 one female Humpbacks were examined for this structure ; the two in which it was present 

 thus give a proportion of 6-4 per cent, which may be compared with the corresponding 

 figure of 6-8o per cent in which tags were found in adult Fin whales. 



