of the Fishery Board for Scotland. 



301 



Almost all the autumn herrings which were above 10 inches in length 

 were ripe or approaching maturity ; and it must be remembered that this 

 was the chief spawning time. 



Some particulars of other cases may be given. In the collection from 

 the Dornoch Firth on 12th November, 1903, thirteen were examined. 

 They ranged from 176mm. to 197mm. (7-7| inches), and their weight 

 from 37.5 to 57 grammes. In all cases the reproductive organ was 

 extremely minute and immature, the heaviest (from a male) weighing 

 0*03 grammes. These herrings were extremely fat, and there was a large 

 quantity of fat in the abdominal cavity. This fat, as I have elsewhere 

 suggested, is probably used up, not only in connection with the develop- 

 ment of the reproductive organs, but also for the production of energy, 

 in tiding over the winter, when growth, and even the power of digestion, 

 is to a large extent in abeyance. 



Other herrings, taken in Aberdeen Bay on 29th December, measuring 

 148 and 153mm. (6 inches) were quite immature and were also full 

 of fat. 



In the spring herring from the Forth, as will be seen later, two series 

 are represented, tha average size of the smaller, but fully mature, fish 

 being about 9| inches, and the range from 8| to about 10 inches. 



I think there is little doubt that these herrings represent shoals spawning 

 for the first time, and that the average size of the winter or spring 

 spawner on this part of the coast, when maturity is first reached, is about 

 23*5cm. (9| inches), while some may spawn when about 21cm. to 22cm. 

 (8| to 8| inches), and others probably not till they are 26 , 5cm. or 28cm. 

 (10 inches), agreeing in respect of variation in size with what obtains in 

 the first mature group among other fishes. In all cases the fish in a 

 group of the same year exhibit considerable variations in length, and it 

 is the average rather than the extremes that have to be considered. 



The mean size I have assigned to the spring herrings when they first 

 spawn is nearly the same as has been given by Hoek for the herrings 

 of the Zuider zee {supra), viz , 24cm. to 27cm., and by Boeck for the 

 Norwegian herring, viz., 25cm. 



It is of some importance to establish the size at first maturity in 

 connection with the consideration of the growth of the fish and the 

 number of annual series which precede the reproductive one. 



3. — Maximum Size attained by the Herring. 



It is also desirable to say something as to the size to which herrings 

 grow. In our waters few are caught over 12 inches (305cm.) in length. 

 In those examined at Anstruther, above referred to, two were 12 J 

 inches (324mm. and 325mm.), and only 33 were above 11 inches. 

 The largest herring that came under the observation of Huxley during the 

 enquiry in Scotland measured 12^ inches (32cm.), and the smallest full, 

 it may be said, was 10J inches (26 5cm.); but he mentions that the 

 Fishery Officer stated that it was not uncommon to get Orkney herrings 

 that measured 14 or 15 inches long, and he had got one of 17 inches 

 (43* 2cm.), a size mentioned by Buckland as the largest for a herring on 

 record. 



At Aberdeen the longest observed by Sim was 12| inches (31 2cm.), its 

 weight being 9| oz.; Matthews (19) got one 33 5cm. long, and another, 

 33'3cm. ; while Brook (20) states that in Lochfyne he has seen herrings 

 in August " quite 15 inches long," or 37cm. 



De Caux (4) records one of 15| inches (39'4cm,), and Murie (21) 

 another of 14| inches (36'lcm.) The largest obtained by Ljungmann (6) 



