908 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [2] _ 
held in high repute. At Naples, near the rocks of Castel, and in other 
deeper parts of the gulf, oysters similar to those of Genoa, are still 
found, which are designated, scientifically, under the name Ostrea plica- 
tula. At neither Genoa nor Naples are the banks sufficiently well 
stocked to permit the use of the drag, with profit, in gathering oysters. 
The fishermen take them by hand, sometimes at a considerable depth. 
The products of this fishery are entirely consumed in the vicinity. 
Rome, Florence, and the large towns of the peninsula receive a part of 
their supplies from Brindisi and Venice, at which places some natural 
beds exist. The oysters from these beds belong to the common Medi- 
terranean species (Ostrea edulis). 
LAKE FUSARO, NEAR NAPLES. 
There is no necessity of our entering here into a retrospective exam- 
ination of the industry of Lake Fusaro. M. Coste, in the learned report 
he has published concerning his mission to the shores of the Mediter- 
ranean, has performed this task better than I could doit. But I have 
thought it proper not to leave Naples without first endeavoring to 
ascertain the causes which have occasioned the sterility of this ancient 
lake and the loss of its secular industry. The principal cause, as well 
as the oldest and most incontestible one, which has at all times occa- 
sioned the greatest disasters, results from sulphurous emanations aris- 
ing over certain portions of the bottom during the eruptions of Mount 
Vesuvius. At such times as these all of the inhabitants of the lake 
are imperiled, but shell-fish suffer most because of their inability to 
get out of harm’s way. At various periods of eruption the oysters of 
Fusaro have been very nearly exterminated, but so great has been their 
fecundity that only a few years were required to enable the lake to re- 
cover its normal productiveness. In addition to this natural and inev- 
jtable cause, there are others of more recent origin and less extent, 
among which may be cited: (1) the accumulation of vegetable and an- 
imal refuse which has fouled the bottom; (2) the too extensive cultiva- 
tion of mussels; (3) the excessive saltness of the water; and (4) the 
insufficient supply of fresh water. Finally, in 1856, the Neapolitan 
Government, with a view to rendering Lake Fusaro more healthy—as its 
marshy water propagated the malady so common in certain parts of 
Italy, viz., malaria—caused a new canal to be dug at the extremity of 
the lake, in order to secure, to the greatest possible extent, the renewal 
of the water. It is claimed that this work hastened the decay of Lake 
Fusaro. The contact of this new current with the old resulted in the 
stirring up of the materials that had been accumulating in the lake for 
many years. Sands were brought down by the current, thus changing 
the nature of the bottom. The oyster-culturists, after vain endeavors 
to overcome this new misfortune, abandoned their concessions, and in 
the year 1869 the last oysters disappeared from Lake Fusaro. 
