294 Part IIL. —Twenty-fourth Annual Report 
that there was no good evidence against the supposition that it reaches 
the spawning condition in one year, a view which was also held by the 
old Dutch naturalist Leuwenhoek. But it might be well, he said, to leave 
the question whether the herring attains its maturity at 12, 15, or 18 
months open, in the tolerably firm assurance that the period last named 
is the maximum. Later, he modified his opinion, agreeing rather with 
Mitchell (2, p. 30) and Yarrell (3, ii., p. 190), that it attained maturity 
when about one year and a half old—a somewhat odd conclusion, since it 
implies that the summer-spawners of one year give rise to the winter- or 
spring-spawners of the next year but one, and vice versa. 
De Caux, who wrote a book on the herring and its fishery, stated his 
belief that herrings arrived at maturity well within twelve months (4, 
p. 50). 
Mr. George Sim did not agree with the supposition that the herring 
grew so fast. From the examination of large numbers of herrings, he 
thought that it grew in its first year six or seven inches, and that it did 
not spawn until the end of its second year (5, p. 46). 
(6) Scandinavian and Dutch. 
On the Continent, and especially in Sweden and Norway, much atten- 
tion has been given to the question. 
Ljungmann (6, 6a), as the result of the measurement of a large number 
of herrings in May from the west coast of Sweden, came to the conclusion 
that the herring grew much more slowly than the above statements would 
indicate. 
On the coast of Bohusliin, where the small herrings come in May, they 
grow rapidly with the high temperature, and measure 80mm. to 100mm. 
He measured a great many herrings in the latter part of November on 
the northern part of the Swedish coast, and found that the length of 
these one-year-old fish varied from 78mm. to 109°Smm. In the latter 
part of spring he also measured many herrings on the Bohuslan coast, 
and came to the conclusion that the majority could be divided into three 
groups, (1) about 120mm. (4? inches), or one year old; (2) 170mm, to 
175mm. (63-62 inches), or two years old; (3) 200mm. to 210mm, (73- 
8+ inches), or, presumably, three years old, and with fully-developed 
reproductive organs. 
Ljungmann occasionally found herrings as small as 18-5em. (74 inches) 
with fully ripe eggs; on the other hand, many herrings from this size up 
to 20cm. (74 inches) could not possibly spawn the same season. While 
he thinks the herring spawns first at three years of age, he says some may 
not do so until four years old. Fish of about 23°5cm. (94 inches) he 
regards as four years old. 
Widegren (7), who assigned a length of 75mm. (3 inches) to a one- 
year-old herring, and a length of 150mm. (6 inches) to one two years of 
age, stated that herrings two months old had a length of 25mm. (1 
inch) and at three months a length of 37mm. (1,/, inches). The size 
at maturity he placed at 20cm. (8 inches) and the age at three years. 
Axel Boeck (8), with special reference to the Norwegian spring herring, 
puts the average length when maturity is reached at 25cm. (9£ inches), 
and the average age at three to four years; while Sundevall (9), dealing 
with the stroémling of the eastern coast of Sweden, supposed them to 
attain maturity when three or four years old, and about 20cm. (8 inches) 
in length. He states that the young herring reach a length of 25mm. 
in about two months; 36mm. in three months; 50mm. in four months; 
75mm. (3 inches) when one year of age, and from 125mm. to 150mm. 
(5-6 inches) when two years old. 
