152 SEA FISHERIES 



the eighteenth or twentieth day." The water of the 

 aquarium was maintained at a temperature of from 

 64*0 to 68*0. But although copious nourishment is 

 indispensable in the case of young fish, it does not 

 appear to be very favourable to the maturing of the eggs 

 of an adult kept in captivity. M. Fabre-Domergue even 

 hinted, at the Congress of Maritime Fisheries, Bordeaux, 

 that the absence of turbots' eggs in the establishment of 

 M. Despommiers was due to the over-richness of the 

 food distributed. The muscles of the fish probably 

 developed more than their ovaries ; indeed, a turbot 

 readily gains from 2j to 5J Ibs. in a year at the Trinite- 

 sur-Mer establishment. 



Marine piscifacture possesses a highly perfected tech- 

 nique of incubation. MM. Fabre-Domergue and Bietrix, 

 in the case of the sole, and M. Anthony in the case of 

 the turbot, have employed a cylinder turning on its 

 axis. This apparatus is partly analogous to that of 

 Chester : a kind of bucket with four openings, the 

 bottom being formed of woven wire. The receptacle 

 containing the eggs is plunged into an aquarium, and 

 the rotatory movement has the effect of continually 

 renewing the water. This process is especially suited 

 to floating eggs. I have no doubt that the incubators 

 used in the culture of fresh-water fish are of great value ; 

 the communicating vessels of MacDonald, the jars of 

 Chase, &c. As for eggs heavier than water (those of 

 the salmon and shad, for example), it is enough to place 

 them on a very fine perforated bottom and immerse them 

 in troughs through which a continual current flows. 

 M. Lestandi has installed at Gradignan, not far from 

 Bordeaux, a model laboratory for the rearing of salmon. 

 The fertilised eggs are placed in a moving cage, which 

 is immersed in a little basin. The mortality of the fer- 



