XXXVI REPORT OF COMMISSIONER OF FISH AND FISHERIES, 



NOTES ON THE SPECIES PROPAGATED AND DISTRIBUTED. 



The Sole (Solea solea). 



May 16, 1888, sixteen English sole were received from Mr. E. G. 

 Blackford, and June 2 twenty more. Thirty-four survived and were fed 

 daily with clams, etc., at the Wood's Holl Station. Mr. Blackford ob- 

 tained the soles from Mr. Thomas J. Moore, curator of the Free Public 

 Museum, Liverpool, England. 



The Flatfish or Winter Flounder (rseudopleuroncctcs americanus). 



This species was found in breeding condition at Wood's Holl, Massa- 

 chusetts, early in February. The eggs were extremely adhesive, and 

 had a tendency to form in large lumps. They were hatched by spread- 

 ing them thinly on panes of glass, and placing them in an aquarium of 

 running water. 1,179,000 eggs were taken, and produced 320,000 fish, 

 of which 220,000 were planted in Vineyard Sound. 



The Cod (Gadus morrhua.) 



Spawning cod were procured for the Wood's Holl Station from Nan- 

 tucket Shoals and Nornau's Land; 155 fish were brought from Noman's 

 Land November 14, and 62 fish from the same place November 17. 

 783 fish arrived from Nantucket Shoals November 17. 



From these were obtained all the eggs that were impregnated at the 

 station. Eggs were taken from November 17, 1887, until February 4, 

 1888. The eggs were stripped into large pans with a moderate allow- 

 ance of water and milted without much loss of time. They were thor. 

 oughly stirred immediately after adding the milt and carried to the 

 hatchery. 30,088,000 eggs were obtained, from which 7,822,000 fry were 

 hatched. The average percentage of production was 26 per cent., and 

 the highest 92J per cent. 



The efforts to transfer the eggs from Gloucester to Wood's Holl were 

 unsatisfactory. For an account of the experiments leading up to the 

 successful hatching of cod at the Gloucester Station see the description 

 of this establishment. 



The greatest number of eggs taken iu any one day during the season 

 was on January 14, when 7,056,000 were collected. 



There is very little variation in the size of cod eggs taken in various 

 places, and from several sizes of fish. 



Mr. Eobinson finds that 1 gallon of water per minute is exactly the 

 amount that should pass through each cod-hatching box in order to 

 make the siphon work properly ; if less goes through the siphon will 

 fail to catch promptly, and if more is used it will not break for some 

 time. 



His best results from the tidal hatching box were obtained with the 

 eggs three layers deep, or 350,000 to the box. The jar seems to be ob- 

 jectionable for cod eggs because of lack of aeration. Eggs of the same 

 age in boxes and jars will hatch out at different times. The box will 

 develop them from five to eight days earlier than the jars. 



