240 RATE OF GROWTH OF SOME SEA FISHES. 



5 per cent, and only a few of these under 2 inclies. The appear- 

 ance of the fry can scarcely be said to have commenced^ only a 

 precocious individual or two having spawned. In April the fry 

 just begin to appear, 14 per cent, herrings are caught, but only 

 12 per cent, of these are scaleless larvas. These must have been 

 one to two months old. The larger herrings, over 2 inches long, 

 taken at this time we need not consider at present. In May we 

 have 30 per cent, herrings and 60 per cent, of these are larvae ; 

 that is, 18 per cent, of the total catch are larval herrings. In June 

 we find that 34'8 per cent, of the total catch are larval herring. 

 In July, according to the figures given, the number of larval herring 

 is increased to 60 per cent, of the total catch, while in August 

 there are no larval forms at all. I am obliged to conclude that 

 there is a mistake in the figures for July ; probably the number of 

 larv[B declines in that month, and it ought to be ''80 per cent, of 

 the herrings caught were over two inches " instead of " under.'' 

 Making this correction we find the larval herrings were 15 per cent, 

 of the total catch. 



If we write down the total number of young herrings under 

 3 inches, the number of scaleless forms, and the number of scaled 

 forms, all as percentages of the total catch, side by side we get — 



Assuming that the alteration I have made is correct we find that 

 the number of larval herrings reached a maximum in June, and 

 that these were almost entirely absent in April and August. It is 

 not clear that the 12*4 per cent, of scaled herrings in April were 

 not over 3 inches long and derived from some spawning in the 

 previous year. Leaving these aside, therefore, we find the scaled 

 young under 3 inches long reach a maximum in July, and slightly 

 decrease in August. But the latter decrease is doubtless only 

 apparent, many of the larger individuals of this season's brood 

 having changed their locality and being no longer caught in the 

 whitebait nets. 



If we had any reliable information concerning a spring spawning 

 of herring at the mouth of the Thames, we could reckon from the 

 time of this spawning the age of the herring fry taken as whitebait. 

 But I have been unable to find anywhere any record of observations 

 on the spawning of herring in this neighbourhood in spring. All 

 that is stated in Holdsworth's work on Deep Sea Fishing and 



