of the Fishery Board for Scotland. 



101 



in the total hard and soft crabs. Again, if we divide the year into two 

 portions, January to June and July to December, we get a total of 1403 

 males and 1401 females in the first half of the year, and 926 hard males 

 and 1006 hard females in die second half of the year. If, however, the 

 soft crabs are included we have 1513 males and 1373 females. The 

 seasonal variation, then, seems to consist in a slight majority of males in 

 the first half of the year, and a slight majority of females among the 

 hard crabs from July to December. There are two factors which may 

 tend to affect the relative number of the sexes caught in the second 

 half of the year. The crabs which hatched their eggs in July and 

 August will either probably cast, or proceed to deep water. The latter 

 then are added to the number of marketable crabs, while the former, 

 remaining soft during a considerable period, will not affect that number 

 till about the end of the year. The ranks of market crabs, however, 

 receive an accession from the crabs which have through casting arrived 

 at a size which admits them to the gauge group. These probably are 

 not hard much before the middle of October. 



With regard to the lobster, ITerrick * says that it is very probable 

 that but little difference will be found in the numbers of the sexes. 



It is very probable that the proportion between the sexes indicated by 

 the beach crabs is more nearly that which exists in the species. The 

 females which are berried seldom appear in the creels, and this fact 

 tends to raise the percentage of male crabs. The statistics of the beach 

 crabs do not suffer from any such sexual selection, and the conclusion 

 is probably warranted that in this species the females slightly exceed 

 the males in number ; to every hundred females there are about ninety - 

 eight males. 



Table IV.— Crabs Collected on Beach at Dunbar between Tide- 

 marks at Low Water of Spring Tides. 





Hard Crabs. 



Soft Crabs. 





Male. 



F'male. 



Male. 



F'male. 



January 10th and 24th, 1898 



February 8th and 22nd, 1898 



March 10th and 25th, 1898 



April 8th and 22nd, 1898 



May 7th and 23rd, 1898 ; 26th, 1899 



June 6th and 20th, 1898 



July 4th and 19th, 1898 



August 4th and 18th, 1898 ; 7th, 1899 



September 2nd and 16th, 1898 



October 12th and 27th, 1897 . . j 



November 11th and 26th, 1897 

 December 10th and 24th, 1897 



53 

 70 

 69 

 63 

 215 

 76 

 72 

 41 

 33 

 84* 

 27* 

 40 

 49 



72 

 92 

 61 

 91 

 188 

 62 

 67 

 30 

 42 

 71* 

 28* 

 39 

 57 



4 



9 

 23 

 47 

 86 

 (28 c? 



72 

 21 



3 

 1 

 1 



5 

 22 

 75 

 68 

 and 2) 



90 

 13 



Totals 



892 



900 



262 



278 



o* 1154; $ 1178. * Includes soft crabs. 



* Op. tit., p. 73. 



