Page 



B. Carp culture upon a large scale 78 



1. Size and division of the necessary pond area 78 



2. The first year 80 



General - production of carp brood and one-summer carps with the 

 aid of spawn ponds, nursery ponds and brood extension ponds 

 (Dubisch method), (a) brood production, (b) growing nursery 

 brood, (c) production of one-sxunmer carps. Production of carp 

 brood and one-summer carps by means of spawning ponds and brood 

 nursery ponds - production of carp brood and one-summer carps by 

 means of enlarged spawning ponds which serve for nurseries, and 

 brood extension ponds - production of carp brood and one-sujffliier 

 carps only by means of brood extension ponds. 



3. The second growth year, rearing of two-summer carps 88 



-i. The third growth year, rearing of table carps , 88 



C. Side-lines in Carp-culture 89 



Value and disadvantage of secondary fishes - the tench - the gold 

 fish - the crucian carp - the pike - the perch-pike - the trout. 



Chapter V. Trout culture 93 



A. Characteristics of the different varieties of trout and environmental 



requirements for their culture 93 



1. General 93 



2. The brook (brown) trout 93 



3. The rainbow trout 95 



/*. The char 98 



B. Artificial Fish Breeding 98 



1. Significance and development 98 



2. Selection and rearing of parent fishes 98 



3. Artificial extraction of the sex products 106 



4. Construction and arraoigement of brood apparatus for the 



artificial hatching of fish eggs 109 



5. Artificial incubation and the shipping of fish eggs. 



The counting of eggs and of brood , J.15 



C. Production of trout fingerlings and adults in trout ponds 121 



1. Rearing of trout fry and fingerlings 121 



2. The culture of adult trout 12^ 



3. Size and division of the pond surface of trout fisheries 125 



Chapter VI. Natural productivity of ponds, their storage capacity 



and the stocking of ponds 126 



Chapter VII. Ush feeding I3I 



A. Importance of feeding. The food quotient as standard of good results ... 131 



B. Tlie most important foods for carps and trout 133 



C. Preparation of foods, manufacture of food mix;tures 133 



1. Carp foods I33 



2 . Trout foods ,,^^ 13^ 



