AND THEIR DISTRIBUTION AT DIFFERENT AGES. 101 



According to Dr. Fulton the smallest ripe dab was 5^ 

 inches long-, and the maximum specimen observed 14 inches 

 long. The smallest ripe specimen seen by me was a male 5*7 inches 

 in length ; the smallest ripe female I have seen was 6*7 inches. 

 The dab spawns in March and April, and in reckoning the ages in 

 the above table I have counted from the month of March. It is 

 certain that the ages given in the above table up to the entry for 

 May 6th, 1889, are correct, and we see, from the sizes of those taken 

 in the summer and autumn, the growth of the fish spawned the 

 same year, while those taken between Christmas and May must be 

 derived from the brood of the previous year, even the smallest 

 taken in May, 1'8 inches, being too large to be attributed to the 

 spawning of the same spring. Thus we find that a dab just 

 over a year old may be as small as 1*8 inches in length ; a conclu- 

 sion not surprising in view of the fact that some of the flounders 

 reared in captivity were only 1*6 inches at the same age. The 

 maximum growth exhibited by this species in a year is more diffi- 

 cult to determine, but considering the case of the flounder we need 

 have no doubt that the specimens 5 inches long, taken on "April 

 3rd, were only just over a year old. Some specimens may very 

 likely reach a greater size than this in the same time. The maxi- 

 mum observed in the flounder was 7^ inches, and as the adult 

 flounder is 2 inches longer than the adult dab, we may provisionally 

 conclude that 5^ inches is about the maximum length reached by a 

 dab in one year. Thus we see that the minimum size, compatible 

 with reproduction, may be reached or slightly surpassed at the end 

 of the first year, but it is certain that the great majority of dabs at 

 one year old are below that size. And it is not certain that those 

 which are large enough to breed at the end of one year, do actually 

 breed then. On the other hand the great majority of even the 

 smallest ripe specimens are of a size that in all probability is not 

 reached by any individuals in less than two years. 



If we examine the entries of specimens obtained from the 

 professional trawlers, we get some interesting results. In the first 

 place we find that the smallest specimens captured are about 4^ 

 inches long. The breadth corresponding to this length is little 

 over 1| inches. The meshes of the great beam-trawl, as used at 

 Plymouth, are 4 inches square at the mouth, diminishing to 1^ 

 inches square at the cod end. Thus there is a close correspondence 

 between the size of the mesh at the cod end and the smallest fish 

 caught. 



We may roughly estimate the growth of the dab in successive 

 years as follows : 



