228 THE SCOTTISH NATURALIST 



or great rarity of other whales upon the Rockall grounds 

 is not so good. That they are as plentiful there as in waters 

 nearer home is, I believe, certainly not the case ; but we 

 must not forget that their carcases are far less valuable than 

 those of the Sperm, and it may well be that it does not pay 

 to go so far for them, or to tow them home from so great 

 a distance. 



Besides those captured on the Rockall and St Kilda 

 grounds, a few stragglers only occurred to the north of 

 Shetland, or in general along the line of the warm current 

 which corresponds roughly to the position of the ioo-fathom 

 line ; and several more occurred in the neighbourhood of the 

 Flannan Islands. 



They were distributed as follows in the several years : 



1908. 1909. 1910. 1911. 1912. 1913. 

 Flannan Islands . . i 7 i 



North of Shetland 



St Kilda 

 Rockall . 



Total 



I ... I 



12 3 I 



5 5 5 



i 7 i 18 8 7 



But while the absence of Sperms around the Shetlands 

 is notable in the earlier years, their apparent absence from 

 these St Kilda and Rockall grounds in these same years 

 may only be due to those distant waters having been as yet 

 little fished or little explored. 



Again we find very great discrepancies in the recorded 

 girths of these whales, as in the case of the Nordcaper, and I 

 am still in doubt how far to attribute these discrepancies to 

 varying modes of measurement, or how far to see in them 

 a real phenomenon. The facts are, briefly, these : The 

 average recorded girth, taking all the individuals together, 

 is 65-8 per cent, of the length of the body, or about 33 feet 

 for a 50-feet whale. But the girths recorded vary from 

 one-third of the length to 86 per cent, thereof, the latter in 

 the case of a whale 44 feet long caught off St Kilda in 191 1. 

 And the various relative girths may be epitomised as 

 follows : 



In other words, our whales apparently group themselves 



