9 o THE COMMERCIAL SEA FISHES OF 



The quantities captured are liable to great variations in 

 different years ; several good harvests may follow one after 

 another, or the reverse may occur ; likewise one set of 

 boats may be making large catches while neighbouring 

 ones are scarcely securing a fish. I have already alluded 

 to there being two classes of mackerel, viz., the enormous 

 May and June shoals that come for spawning and consist 

 of large fish, and the more erratic or in-shore and smaller 

 ones that do not appear to keep so well to stated times : 

 the modes of capture of these two classes vary. The nets 

 employed in the English Channel are for the in-shore or 

 smaller forms, the mesh of which before being tanned 

 averages from 27 to 28 half-meshes to a yard ; but those 

 employed at the entrance of the channel for the spawning 

 shoals average (untanned) from 21 to 22 half-meshes to a 

 yard. 



Early in the spring numerous fishing boats, manned with 

 from five to eight men each, assemble in Plymouth pre- 

 paratory to the mackerel season, and for the purpose of 

 trying their fortune in the English Channel with drift-nets, 

 which are shot of an evening and usually lifted after two 

 or three hours, but shot again in the very early morning, 

 the best time for carrying on this occupation having been 

 found to be when daylight passes into darkness, or the 

 night into the morning. The fishermen believe that at the 

 commencement of the season the vision of these fishes is 

 not so good as it becomes later on, when, however, it may 

 be materially assisted by lighter days and moonlight nights, 

 while it has been observed that the fat which is found in 

 the early months of the year between the two layers 

 forming the adipose lid to the eye, becomes absorbed as 

 the season advances. It has been remarked that drift-nets 

 are less productive during bright moonlight than when the 

 nights are darker, as the fish are believed to perceive and 



