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Part III. — Ninth Annual Report 
cruises were made off the coast of Sclileswig-Holstein and Denmark, 
northwards to the Skagerrak and westwards to near the most eastern point 
of the Dogger Bank. Fully ripe herring were found in the Skagerrak, 
north of the Jutland Bank. Dr Heincke believes these to be identical 
with the well-known Swedish Bohuslan herrings ; and other observations 
make it probable that a large number of the latter are composed of fish 
which spawn in September on the south coast of the Skagerrak. Traces 
of ripe autumn herring were also obtained a little to the north of Heligo- 
land. The Germans, who take the greater proportion of the Scotch-cured 
herrings exported, are fully alive to the im})ortance of discovering 
spawning-grounds for the herring off their own coasts. Dr Lindemann 
states that at present Germany imports foreign salted herrings to the value 
of over £1,500,000 yearly, while the annual value of the native catch is 
only about £15,000. During the cruises of the 'Sophie' physical 
observations were made, and collections obtained of the bottom and 
pelagic fauna and flora. Considerable immbers of small immature fish 
were got far from land, a circumstance bearing upon the location of 
spawning-grounds and nurseries. The results obtained by Dr Reinke as 
to the absence of algse on the bottom in large areas of the North Sea 
were fully confirmed. The Jutland Bank and the Little Fisher Bank 
were completely ))arren. The conclusion is, that the rich fauna ulti- 
mately depends for subsistence mainly upon pelagic microscopic plants. 
The Fishery Department also possesses a marine laboratory, where 
scientific investigations have been for some time carried on by Dr Ernst 
Ehrenbaum, who recently published an elaborate monograph on the 
common shrimp, illustrated by four plates."^ The structure and develop- 
ment of Crangon are described in great detail ; and much information is 
given as to the reproduction and habits. An account is also furnished of 
the fishery in the North Sea. Dr Ehrenbaum's researches appear to show 
that there are two principal spawning periods, the first being from the 
middle of April to the beginning of June, and the second in October and 
November. The eggs of the former period hatch in probably about four 
weeks, the time depending principally on the temperature of the water, 
the hatching beginning about the end of May, and continuing well into 
August. The eggs extruded during the second period are carried through- 
out the winter, and begin to hatch in February, most of them being 
hatched in April. Hence the smallest percentage of ' berried,' or egg- 
carrying, females is in August or September. As a rule, the same female 
does not spawn twice in one year, but this sometimes occurs. Dr Ehrenbaum 
notes the great numerical preponderance of females over males cap- 
tured. The food of the shrin)p differs very much in the young and 
in the adult, since the larvae lead a pelagic life in strong sea-water ; 
the adults in the warmer months come into brackish water. The 
fully-developed shrimp lives partly on algse, but mostly on animal matter, 
such as annelids, small crustaceans, &c. A point of interest is that 
Dr Ehrenbaum frequently found the remains of larval fishes in their 
stomachs, especially herrings and smelts ; in one case nearly an inch long. 
In regard to the utility of instituting a close-time for shrimps (a measure 
recently advocated in Oldenburg), Dr Ehrenbaum thinks, from his know- 
ledge of their habits, that it would be practically useless. The shrimp- 
fishing with bow-nets {reusen)^ fixed nets, push-nets (schiebe), and trawls 
(schle/jpTietzen) calls for no interference ; but the fishing with baskets or 
traps does. While the sieve used to separate the marketable from the 
unmarketable shrimps has meshes 7*5 millimetres wide, the traps (korhe) 
in which the shrimps are caught have meshes only 2 millimetres wide 
* Zur J^aturgeschichte von Crangon Vulgaris, Fabr., Berlin, 1890. 
