DESTRUCTION OP IMMATURE FISH. 155 



of long rough and common dabs taken^ wlietlier mature or immature, 

 is of no great importance. Neither species is valuable, and though 

 eaten they are only sold at a very low price to the poorer classes of 

 certain districts. Thus, of the w^hole number of 11,613 fish classed 

 as immature, as many as 10,342 belonged to nearly worthless species. 



Prof. Mcintosh's observations were carried out on trawlers work- 

 ing in the ordinary course of business in the following localities : 

 St. Andrews Bay, Aberdeen Bay, off Smith Bank, the Firth of 

 Forth, off Scarborough. 



Similarly Mr. Cunningham, the Naturalist of the Marine Biological 

 Association, has made frequent observations on trawlers engaged in 

 their business off Plymouth and westward to Mount's Bay. His 

 experiences in all seasons and in all weathers coincide very closely 

 with those of Prof. Mcintosh. Very young flat-fishes are not cap- 

 tured in the large beam trawls working in depths of thirty to forty 

 fathoms. Flat-fishes somewhat less than six inches in length are 

 not uncommon, but they invariably belong to worthless or nearly 

 worthless species, and of these no specimen under three inches long 

 has been noticed. 



The more valuable species of flat-fish taken by Plymouth trawlers 

 are the sole {8oIea vulgaris) , tarhot {BJiomhus maximusY hriW {Rhotn- 

 hus lasvis), merry sole {Fleuronectes "niicrocephalus) , megrim [Arno- 

 glossus megastoTYia), plaice (Fleuronectes jplatessa) . Mr. Cunningham 

 has never seen any of these species less than six inches in length 

 brought up in the beam trawl. But there are several smaller 

 species of little marketable value of which numbers of small speci- 

 mens are commonly caught; these are flounders [Fleuronectes jlesus) , 

 dabs {Fleuronectes limanda), thickbacks {Solea variegata), and scald- 

 fish [Arnoglossus laterna). As the staff of the Marine Biological 

 Association has been engaged on other problems, these fish have not 

 been regularly counted and measured, but in the matter of flat-fish it 

 is obvious that there is no difference between the north-east coast of 

 England and Scotland and the channel near Plymouth. In both 

 cases large numbers of undersized flat-fish are caught, and in both 

 cases they are composed nearly exclusively of worthless species. The 

 long rough dab [Rippo gloss aides limandoides) is an exceedingly rare 

 fish on the south-west coast of England, and its presence in the one 

 and its absence in the other case forms the principal difference be- 

 tween Prof. Mcintosh's results and those of the Marine Biological 

 Association. In Prof. Mcintosh's experiments 596 immature plaice 

 were captured, and these principally in St. Andrews Bay, in depths 

 varying between four and a half and twenty fathoms. It has been 

 seen that very few small plaice are caught in the beam trawl at Ply- 

 mouth, but quantities are caught by other means, as will appear later. 



