114 EATE OF GROWTH OP SOME SEA PISHES 



with an otter-trawl myself, on purpose to obtain young fish, I have 

 obtained large numbers of this species from 3 to 5 inches in length. 

 I find that specimens of this size are between one and two years in 

 age, are not sexually mature, and are distributed at all depths from 

 3 to 40 fathoms. 



Pleuronectes microcephalus, the merry-sole, is the only other 

 species of the genus usually met with near Plymouth. There is 

 no doubt that the young, under 6 inches long, and less than one year 

 old, are entirely absent from shallow water, under 10 fathoms, and 

 from inlets and estuaries. No destruction of the young of this 

 species can be effected by shrimp^ or seine, or bag-net fishing in 

 territorial waters. As far as my observations go, the professional 

 deep-sea trawler does not capture the young of this species under 

 6 inches, but on this point I have collected very few data up to the 

 present time. It is, however, certain that the species belongs to 

 rather deep water ; it is scarce at less than 30 fathoms, and abun- 

 dant at greater depths. I have not yet obtained any specimens 

 under 6 inches long, but Dr. Fulton obtained three specimens, 2 

 inches long, at about 20 fathoms. I have not met with any such 

 specimens in my numerous hauls with small-meshed trawls this 

 summer inside the Eddystone. I am inclined to think that most of 

 the young of this species, when they go to the bottom, remain in 

 deep water beyond the 30 fathom line. 



I have not yet found young soles between ^ inch and 6 inches in 

 length, although I have specially searched for them at various depths 

 up to 35 fathoms. My evidence concerning this species is similar 

 to that concerning the brill and turbot ; in all three cases I have 

 found the very young forms only a few weeks old close to the shore 

 in harbours and inlets, and have taken other specimens much larger 

 and about one year old in territorial waters within the 10 fathom 

 line. 



With regard to the age of sexual maturity, I have proved that 

 a large number of individuals do not reach the minimum size of 

 mature specimens at the end of one year, and that it is quite 

 probable that all flat fishes normally breed for the first time when 

 two years old. 



2. Other species. — It will be seen that the young of all the species 

 of Gadus mentioned above, namely the whiting, pollack, pout, and 

 poor-cod, for the first six months of their existence are found close 

 to the shore, the fry of the pollack and poor-cod seeking harbours 

 and estuaries, and being seen in numbers swimming about near 

 piers and wharves. When about one year old, these kinds of fish 

 are found in abundance at depths of 5 to 30 or more fathoms. 

 The pollack haunts rocky shores all its life, and only very large 



