140 EEPORT OF COMMISSIONER OF FISH AND FISHERIES. 



itself- nevertheless we deem advisable not to overlook any of the gen- 

 eral considerations which are the f-esnlt of direct and experitneiital ob- 

 servations made on the systems of fishing in the Gulf of Naples. If, 

 on one side, we view these considerations as only partial regulations 

 relating to local facts, on the other side we find them placed among the 

 general tacts which furnish the elements of the law itself. 



In order to judge of the fitness of the systems of fishing, we must 

 consider them under three aspects: the means to be employed, the 

 proper seasons, and the proper places ; three things that are so united 

 that one cannot be separated from the others, and means which in 

 themselves might be harmless if employed in proper seasons and places, 

 become very injurious to marine productions when used out of season 

 and place. 



The general rules which a wise regulation for fishing must prescribe, 



are : 



1st. Fishes should not be molested during the time of spawning. 



2d. The eggs should be left to rest where they were deposited, so as 

 not to be disturbed during their develoi)ment. 



3d. The young must not be destroyed till they have reached a certain 



size. 



4th. Fishes must not be destroyed in mass, by means of poisoning. 



From these incontestable principles it foUows, as an evident deduc- 

 tion, that a regulation for fishing must prescribe: 



1. That fishing must not be carried on in times and places when and 

 where fishes meet for the deposition of eggs or spawn. 



2. Dragging-nets must uoc be used in seasons and places in which 

 eggs are in process of hatching, or embryos undergoing development. 



3. Nets with too close meslies must not be used, because they gather 

 the very small fishes, and thus prevent them from developing sufficiently 

 to become useful to consumers. 



4. No substance must be used which, when thrown in the sea, pro- 

 duces such changes in the water as to cause the death of all the fishes 

 therein. 



The third and fourth of the above rules find their application equally 

 in every country, but the first two retiuire for their application an exact 

 knowledge of the instincts of fishes iu regard to their spawning, and of 

 the nature of the bottom of the sea. 



The general rule, that fishing must be carried on in such a manner as 

 not to affect the continued production, contains certainly, in itself, all 

 that can be required. It otteu happens, however, that general rules are 

 easier iu theory than iu practice. 



As regards the apparatus of fishing, the greatest care has been deemed 

 necessary, from remote times, in the use of trawl-nets, which, raking 

 over the bottom of the sea so as to gather up the mud in seasons iu 

 which the eggs are deposited, destroy everything, thus causing much 

 damage to the reproduction of the species. Hence the permanent pro- 

 hibition of the use of such nets from Ai)ril till October, which is found 

 in the fishing regulation in the old Neapolitan provinces. The fact of 

 the damage which is caused to marine productions by the use of trawl- 

 nets iu the seasons above mentioned is so evident to us that it seems 

 useless to attempt to argue the question, especially as we would only be 

 repeating what has already been demonstrated so learnedly by others. 

 We think, however, that iu examining such arguments we must not 

 confine ourselves to the trawl-net, but must take into consideration the 

 whole category of meshed nets. We must undoubtedly make a distinc- 

 tion between those which drag heavily the bottom of the sea, thereby 



