226 Part III — Seventeenth Annual Report 



In August, as has been said, the increase in the larger adults is still 

 more pronounced. Thus the percentage of those at or over 12 inches in 

 length rises to 25*6, more than three times what it was in June ; the pro- 

 portion of those at or over ten inches rises to 42*1 per cent., nearly double 

 what it was in June; those over nine inches form 56 per cent, of the shoals, 

 those under nine inches amount to 44 per cent., and those under eight 

 inches to 28*9 per cent. The feature of the month is the increased 

 abundance of the larger adults. In September, the proportion between 

 the adults and the immature reverts to what it was in June, the percentage 

 of those over nine inches in length being 39*8, and of those under nine 

 inches 60'2. The proportion of large adults is still, however, high — 

 viz., 19'5 per cent., those over ten inches amounting to 35*1 per cent. 

 The special feature is an increase in the numbers of small gurnards, those 

 under eight inches amounting to 48*6 per cent., the highest of the year, 

 and it is chiefly caused by an increase in those at four and five 

 inches, the percentage of which rises to 29*7. In October the percentage 

 of the adults and immature is exactly equal. The proportion of 

 large adults is still higher, and the special feature is the diminution 

 in the numbers of the smaller gurnards under five inches, which is 

 also marked in November, when the proportion of adults and of large 

 adults rises to approach what it was at the beginging of the inshore 

 migration. Thus the adults appear to remain longest in the inshore 

 waters ; they come first and leave last. The immature forms come in 

 later and leave sooner. The proportions of the different sizes in the 

 various months are given in Table V. : — 



Table V. 





5 Inches 

 and under. 



Under 

 8 Inches. 



Under 

 9 Inches. 



9 Inches 

 and over. 



10 Inches 

 and over. 



12 Inches 

 and over. 



March, 





7.1 



7-1 



92 9 



92-9 



71-4 



April, 



0-3 



9-7 



24-4 



75-6 



65-9 



31-3 



May, . 



8-1 



36-6 



58-8 



41-2 



29-6 



10-2 



June, . 



4-1 



43-3 



60 -5 



39.5 



22-2 



7-8 



July, . . . 



21-2 



45-3 



58-6 



41-4 



30-3 



14-4 



August, 



10-3 



28-9 



44-0 



56-0 



42-1 



25-6 



September, 



297 



48-6 



60'2 



39-8 



35-1 



19-5 



October, 



137 



40-7 



50-0 



50-0 



43-4 



26-8 



November, . 



15-9 



31-7 



337 



66-3 



53-9 



27-0 



Two points may be specially considered in connection with the above 

 facts, first, the increase in the number of adults in autumn, and second, 

 the migrat'on of the immature gurnards into the inshore waters. 



With regard to the former, it appears probable that towards the end of 

 July new shoals of spawning adults make their way into the inshore 

 waters. The relative increase in the numbers of these large gurnards is 

 also an absolute increase; that is to say, the average per haul of the trawl 

 is higher, as well as the percentage proportion. Thus the average per 

 haul of those at or over nine inches, ten inches, and twelve inches in the 

 various months is as follows : — 



