THE REPRODUCTIVE ORGANS 379 



infection by some micro-organism then sets in, resulting eventually in the formation 

 of the pit. Callorhynchus, for instance, is a fish with remarkable projecting teeth, but 

 there is still the difficulty that the walls of the pit are normally absolutely vertical at 

 the edge (i.e. at right angles to the surface of the blubber), and it is difficult to imagine 

 any kind of teeth even starting such a wound. 



The presence of pits and scars on whales from widely separated localities such as 

 New Zealand, Ecuador, South Georgia and South Africa, gives a kind of unity to the 

 southern whales. It shows a common experience confined to whales in the warmer 

 water of the ocean, leaving its mark on the whales that migrate. It strengthens the 

 theory of a north and south migration between the temperate or sub-tropical waters 

 and the Antarctic and sub-Antarctic regions. 



The open pits seem never to have been described in whales of the northern hemi- 

 sphere . They are mentioned neither by True ( 1 904) nor by Sars ( 1 878 , 1 880) and they do 

 not appear to be present on the whales of which True shows photographs . Irregular grey 

 patches on the flanks and white patches on the ventral grooves are mentioned by these 

 authors, but this is probably concerned with the normal colouring of the whales. 

 White scars are mentioned by CoUett (19 12) on Sei whales from West Finmark and 

 by Burfield and Hamilton on Fin whales from Bellmullet, Ireland. From Burfield's 

 description of "large oval grey spots with radiating dark lines 2i in. x li in.", one 

 would perhaps suppose that these whales had at some time suffered from open pits. 

 More than one kind of scar, however, is liable to appear on the skin of whales, and 

 further observations are needed from northern stations before the point can be settled. 



IV. THE REPRODUCTIVE ORGANS 



The systematic examination of the genitalia includes some of the most important 

 observations in the work at whaling stations, and certain aspects of the physiology of 

 the reproductive organs must be examined in considerable detail. 



Previous descriptions of the genitalia of Cetacea have been few, and for the most 

 part, not very helpful. Turner (1871) describes the uterus and foetal membranes of 

 Orcinus, but the paper by Meek (1918) on the reproductive organs of the porpoise and 

 some other species is probably the most useful general description though this does 

 not include any account of Blue and Fin whales. 



Since there is no difference of any importance between the genitalia of Blue and 

 Fin whales the following account may be considered to have a general application 

 except where otherwise indicated. 



THE EXTERNAL GENITALIA 

 There is not very much to be said with regard to the external genitalia, but 

 systematic notes have been made on them and their appearance sometimes gives a 

 little information on the sexual condition of the whale. In the female the vulva is 



