of the Fish&ry Board for Scotland. 



13 





Plaice. 



Cod. 



Lemon Soles. 



Turbot. 



Others. 



Total. 



1894 



26,060,000 



500,000 



... 







ri/? f £?a r\f\r\ 



26,560,000 



1895 



38,615,000 



2,760,000 



4,145,000 



3,800,000 



1,050,000 



50,370,000 



1896 



11,350,000 



750,000 



1,580,000 



1,360,000 



950,000 



15,990,000 



1897 



24,370,000 







... 





24,370,000 



1898 



19,200,000 











19,200,000 



1899 



16,470,000 











16.470,000 





136,065,000 



4,010,000 



5,725,000 



5,160,000 



2,000,000 



152,960,000 



At the close of the season's work the hatchery was dismantled 

 and transferred, with the apparatus, pumps, and plant, to the new 

 site at the Bay of Nigg, Aberdeen, and re-erected there. The large 

 concrete tank, referred to iu the preceding Eeport, was completed 

 towards the close of the year. It was found to work satisfactorily, 

 and as it has a capacity of about 160,000 gallons, and is so sunk in 

 the ground as to admit the sea, through a twelve-inch pipe, at half- 

 tide, it ought to be able to contain a large number of spawners, and 

 will form a valuable adjunct to the establishment. The collection 

 of adult plaice for the ensuing hatching season was begun in 

 December. An additional concrete tank to contain about 60,000 

 gallons of water was built on an elevated part of the site, to act as 

 a reservoir to supply the hatching apparatus in the night 

 during the hatching season, and the tanks in connection with the 

 laboratory at other times of the year. 



The Life History of the Edible Crab. 



In the present Eeport will be found a paper by Mr. H. C. 

 Williamson, describing the results of an investigation into the life- 

 history of the edible crab, which he has conducted during the past 

 two years. The edible crab is one of the shell-fish which have 

 formed the subject of legislation, the Fisheries (Oyster, Crab, and 

 Lobster) Act of 1877 having prohibited the sale or possession of any 

 crab of less than 4=\ inches across the back, of any soft crab, 

 or of any crab with the spawn attached ; and since then the District 

 Fisheries Committees in England have made many bye-laws still 

 further regulating the fishery in that country. At the same time 

 it has been felt that much fuller information than existed concern- 

 ing the life-history and habits of the crab is required in order to 

 follow the operations of these regulations ; and it was principally 

 with this object in view that the research was begun. 



The result of this research is to throw a considerable amount of 

 light upon such important problems as the size at maturity, the 

 seasonal migrations, distribution, and the season of casting. It 

 was found that a female crab may be potentially mature when it 

 measures about 4J- inches across the broadest part of the back ; 

 many between this size and 5-J inches, probably about a half, are 



