TRAWLING IN BAYS ON THE SOUTH COAST OF DEVON. 321 



or predatory forms. The balance appears to have been upset by the 

 interference of man, but it is very difficult to advise how it may be 

 satisfactorily adjusted again. 



There is some risk even in the assertion that such worthless and 

 predatory forms as sharks and dog-fish are wholly noxious, since their 

 depredations among valuable fish may be partly compensated by the 

 destruction which they inflict on each other and on small competitive 

 forms. I am nevertheless inclined to think that the dog-fish commonly 

 met with by trawlers, spur- dogs, nurse, rough -dogs, and angels or 

 buffoons, do more harm than good, and may safely be killed when 

 encountered. From the results of enquiries which I have made I doubt 

 whether trawlers take any trouble in this matter. Spur-dogs, perhaps 

 the most destructive of all, are likely enough to succumb to exposure 

 on deck before they are shovelled overboard, but nurse, rough-dogs and 

 buffoons are very tenacious of life, though easily disposed of by the 

 judicious use of the heel of a sea-boot. 



I have endeavoured to set forth above all the more important points 

 raised by our enquiry, in so far as they can be limited to the single 

 industry of trawling. I see no reason to change the opinion which I 

 have long held, that the practical treatment of questions dealing with 

 the supply of flat-fish cannot be limited to trawling alone, but must 

 embrace all fisheries which are prosecuted on any part of the area 

 tenanted, at different phases of their life history, by these fish. 



