382 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



4. When the lisli lie on the side it is usually a sign that tbey are sick, 

 or do not have enough pure water. 



5. I do not know the nature of food used, or, judging by the sample, 

 whether it is the best for the purpose. 



6. The goldfish will spawn in an aquarium, but in order to give them 

 a chance to deposit their eggs in a safe place, there should be a water- 

 plant, upon which the females will discharge their ova, and to which 

 they will adhere, and on which they will hatch out. 



7. Those with the tails "seeming to shed" have i)robably had the 

 skin abraded or injured by rough usiige. 



8. There is nothing that can be put in the water that will make the 

 fish healthy. Avoid nostrums, but make the conditions of life normal 

 to the fish and they will thrive. It has been the writer's experience 

 with large goldfish that if there are enough of water-plants io a spacious 

 tank, or even if the sides are merely coated with an abundance of mi- 

 croscoi)ic green algte, that they will take little food which they may be 

 oftered and live apparently in perfect health for years. Too many 

 plants in the water are just as bad as none at all. The plants give off 

 oxygen to the water, which is of advantage to the fish. 



Washington, D. C, Ajyril 13, 1883. 



187.— EXPORTS OF FISII.Oir, FROITI IVORWAY, 1878-'8«. 

 By FREDRIK M. TVAI.I.E]^I. 



[From a letter to Prof. S. F. Baird.] 



As far as now known, the exportation of fish-oil (including whale-oil, 

 &c.) has been as follows : 



Tears. 



1878 



1879 



1880 



1881 



18812 (January 1 to October 31) 



Liters. 



Gallons. 



* This is calculatod on the basis of the United States standard gallon of 231 cubic inches, which con- 

 tains 3.785 liters. The liter contains 61.028 cubic inches. 



The proportion of cod-liver oil in 1882 was less than in other years, 

 as the whale and other fisheries were more successful than usual. The 

 quantity of cod-liver oil exi)orted must be over 60 per cent of the 

 whole, while the cod-liver oil for medical purposes (three grades) is at 

 least 33 per cent. The price of this oil for medical purposes fluctuated 

 greatly in Europe during the spring of 1882. At present the price of 

 the best grade (" steam refined") is $20,80 per barrel. During 1881 its 

 average price was $22.25. 



Bergen, Norway, December 21, 1882. 



