[11] TRANSFORMATION OF SALT MARSHES INTO FISH-PONDS. 527 
author says: “Intermittent fevers to which people living in a marshy 
country are generally exposed are not frequent at Comacchio ; and when- 
ever there are in the neighboring country any young people with a 
feeble constitution or threatened with consumption, they are sent into 
the marshes for the purpose of gaining strength, and are made to share 
the work and food of the fishermen.” 
Competition.—In a petition addressed to the minister of marine, the 
proprietors of fisheries, especially those of the district of La Teste, have 
thus expressed their grievances: 
“During winter, when the scarcity of fish would allow us to realize 
some profit, we are deprived of this advantage by the number of fish 
from the fish-ponds which are brought to the Bordeaux market.” 
This was followed by a request to have the fish-ponds abolished, so 
that with them all competition might disappear, and the greater scarcity 
of fish bring about a corresponding rise in prices. 
To expose such pretensions means to denounce them. Without seek- 
ing to refute them, we feel nevertheless constrained to say that this com- 
petition which has been denounced in such a manner does not exist at 
‘all, neither in the fish-market nor in the fisheries. 
As regards the fish-market, it must be said that the ponds only furnish 
fish during winter, therefore at a time when bad weather has rendered 
fishing impossible, or at least prevents the fisheries from fully supplying 
the demand. 
As regards the fisheries, it must be said that when the mullet enters 
the fish-ponds it measures, generally, only 6 centimeters in length and 8 
millimeters in breadth. If caught by the fishermen these young fish 
would uselessly perish on their hands; it has, therefore, been found 
necessary to probibit the fishing of young mullet. In the fish-ponds, 
on the other hand, the mullet is left in peace, and finds all those con- 
ditions which favor its preservation and development. Left to itself in 
the basin of Arcachon, the young mullet is often thrown by. the tide on 
the shore, where it invariably perishes, and in’ nearly every case falls 
a prey to voracious animals, most of which are of no use whatever to 
man. 
The fish-ponds, therefore, tend to utilize for the food of man products 
which otherwise would, to a great extent, be lost. 
The young fry of the mullet, during the first stages of their devel- 
opment, remain in the basin of Arcachon. As soon as frost sets in, 
they leave this basin and seek deep and sheltered places farther out at 
sea. Their migration commences in November, and at that very time a 
large number of fish of prey are observed, notably hake, which, by 
their instinet, are led to the entrance of the Arcachon Basin, where they 
find an enormous number of young fry, especially of the mullet kind. 
On opening these hake their stomachs are found filled to repletion with 
young fry, particularly with young mullet. Before the migration of the 
