1116 EEPORT OF COMMISSIONER OF FISH AND FISHERIES. [16] 



mers' carp, &c. During the autumn of the year in which they are born, 

 and till the following spring, the carp are one summer's carp, in the 

 following autumn and spring they are two summers' carp, &c. These 

 terms cannot possibly be misunderstood. It will be much more incon- 

 venient to distinguish the carp by the number of years, for in order to 

 avoid confusion the two summers' carp would have to be called one and 

 one-half year old in November, one and three-quarter year in February, 

 two years old in May, &c. 



As small fish do not flourish if put in one and the same pond with 

 larger fish of the same kind, because they will thus be deprived of some 

 of their food, it will be welt to have different raising-ponds for carp of 

 different years, whilst when the carp have grown to a larger size, it is 

 no longer necessary to keep them separate. 



One summer's carp are placed in spawning-ponds of the first class and 

 two summer's carp in those of the second class. To accommodate my. 

 self to the terms employed in Dubisch's method, I have called those 

 ponds to which the fish are repeatedly transferred during the first sum- 

 mer, "raising-ponds for fry," of the first and second class. 



The raising-ponds i^roper of the first class should, if possible, resemble 

 the spawning-ponds and '^ raising-ponds for fry" as to location and char- 

 acter. They may, however, be much larger, and cover an area of several 

 hectares ; in accordance with the size of the fish, their depth may vary 

 from ^ to 1 meter. Their edges should be flat, and be planted with 

 Glyceria fiuitans. A moderate quantity of reeds (iyplia) and lilies (iris) on 

 the edges of the pond will not only be an ornament, but also cause the 

 development of various low grades of animals which serve as food for 

 the fish. In raising-ponds fed by rivers and lakes, aquatic plants, such 

 as Potamogeton, Lemna, and others, will soon make their appearance, 

 which in moderate quantity are very desirable, but which should not be 

 allowed to grow too rank. Eaising-ponds may be used for watering cat- 

 tle, as their dung deposited in the water favors the development of 

 infusoria, insects, &c., and as there is no longer any danger that the 

 fish will be injured thereby. No other fish besides carp should be 

 allowed in the raising-ponds. According to the quantity of food con- 

 tained in the ponds, from 300 to 800 one-summer's carp maybe counted 

 per hectare, which, if weighing 10 grams each when placed in the pond, 

 should in autumn reach a weight of one-half to one pound. According 

 to Dubisch's method, the raising-pond intended for one-summer's carp 

 (which have reached a weight of one-quarter pound in the "raising- 

 ponds for fry") is stocked with 520 fish per hectare. These, in the 

 autumn, when their number has decreased to 500, should weigh 1 to 1^ 

 pounds each. 



The raising-ponds of the second class, intended for two-summers' carp, 

 may be larger and deeper than the former class, and also contain more 

 plants. As a general rule, they are stocked with from 200 to 400 carp, 

 weighing one- half to one pound per hectare, which in autumn will have 



