﻿Variation in the Norway Lobster. 133 



the sexes, for I had previously recorded ^ measurements of 

 length for 656 Norway lobsters from the Clyde, in which it 

 was found that the average length of males was greater than 

 the average length of females, and that while only one female 

 I out of the 656 had a greater length than 160 mm., no fewer 

 than 41 males exceeded that length. It is therefore 

 interesting to know that what was found in the limited 

 number of Clyde specimens is even more marked in the 

 East Coast ones. 



The comparative length of the different sexes is further 

 emphasised in Table II., which summarises the present as 

 well as the previous i esults on this point. From this Table 



Table II. 



Percentages of Sexes at Different Lengths. 



Maximum Length in 

 Centimetres. 



East Coast Norway Lobsters, 

 giving Percentages between 

 different lengths. 



Clyde Norway Lobsters, 

 giving Percentages between 

 different lengths. 





Males. 



Females. 



Males. 



Females. 



Up to 8 cms. 



1-7 



16-4 



22-0 



34-1 



9 to 12 cms. 



18-3 



64-3 



28-8 



38-3 



13 to 16 cms. 



50-4 



18-6 



36-4 



27-3 



Upwards of 16 cms. 



29-6 



0-7 



12-8 



0-3 



Totals, 



100 



100 



100 



100 



it is seen that less than 1 per cent, of the female, and nearly 

 30 per cent, of the male, Norway lobsters here examined 

 are over 16 cms. in length. On the other hand, 20 per cent, 

 of the males, as against over 80 per cent, of the females, are 

 under 12*5 cms. in length. From this one seems justified 

 in concluding that the male Norway lobster is in general 

 longer than the female. 



'^Proceedings of the Cambridge Phil. Soc, vol. xii. , part v., pp. 441-444 

 (1904). 



