REPOPULATION 137 



causes the entrance of the fish in the spring, and a 

 current running from the sea into the lagoon, which 

 brings out the fish in the autumn. But although the 

 gates are open in the spring to receive, they are closed in 

 the autumn to retain. The fish cannot reach them, for 

 upon their way through each basin they encounter nets, 

 fashioned in compartments, numerous, and provided with 

 basket-traps, in which they remain captive. There are 

 five species caught in these basins bass, grey mullet, 

 gobies, atherine, and eels. 1 According to MM. Schmarda 

 and Gobin, a kilogramme (2-2 Ibs.) of eel fry, consisting 

 of 3,600 young eels, will in three years acquire a weight 

 of 6,000 kilogrammes (nearly 6 tons) and a value of 120 

 to .140. A kilogramme-weight of mullet will include 

 20,000 young fry. At the end of a year half will be dead, 

 but each will weigh a third of a pound. The annual 

 yield of the lagoon varies from 48 to 55'6 Ibs. per hectare 

 about 19 to 22 Ibs. per acre. 



The Italians give the name of valle to any lagoon 

 devoted to the breeding of fish. In Venetia, according 

 to Mr. Thorndike-Nourse, there are more than 175 valli. 

 They are remarkable by the complexity of their channels, 

 which turn like the paths of a maze and are known as 

 cogolere ; by the presence of a canal, or circondaria, 

 which, surrounding the lagoon, serves as a refuge to the 

 fish during the great heats and provokes a perceptible 

 movement of the waters which is propitious to aeration ; 

 and, finally, by the deep moats and ditches which serve 



1 The tolerance of fish for sea-salt is remarkable. Taking the 

 litre as the unit of measure or 1,000 parts here is a list of the 

 quantities of salt which the principal species living in the lagoons or 

 fish-ponds are capable of supporting : Eels, o to 40 ; bar, 10 to 40 ; 

 mullet, 16 to 40 ; plaice, 20 to 40 ; sole, 25 to 40 ; golden mullet, 

 24 to 35 ; blind mullet, 5 to 40. 



