— 5 
(Sb) 
Such examination was therefore commenced at the Laboratory by BrocH, who has 
examined numerous samples from the Norwegian coastal waters and from the different 
parts of the North Sea. 
Broch’s investigations as to mixture of races. 
Brocu’s*) investigations in regard to race confirmed on the whole the results arrived 
at by Herncke. Brocs found, as did HEInckE, a distinct racial difference between 
the ocean herrmg of the North Sea Banks (Shetland, Dogger, and Bohus herring) and 
the ocean herring off the Norwegian coast, (spring, large, and fat herring). 
As regards the North Sea herring, Brocu’s investigations furnish, as he himself 
points out, but little new information; in the case of the Norwegian coast herring, howe- 
ver, he is able to make far more definite statements, having had an essentially greater 
quantity of material at his disposal than HEıncke. Brocu points out first of all with 
certainty, that the greater part of the herring in Norwegian coastal waters belong to 
one and the same race, corresponding in all essentials to the marks of racial distinction 
described by HEıncke. He also points out that there exist in different fiords, as for 
instance Trondhjemsfjord, local races, small spring spawning fish, which may perhaps 
be compared with HEINCKE’s coast forms (see above). 
Brocu then examined the mixed samples from the north-eastern part of the North 
Sea, sorting the samples according to the degree of developement of the genital organs. 
The samples from the Viking Bank, already mentioned**) as taken at the end of October 
and beginning of November 1905, were thus found to consist of two groups, one having 
genitals at Stages II and III, or approaching the stage of the “full” herring, the other 
group exhibiting genitals in a state of exhaustion (spent fish). Investigations as to the 
racial characteristics, (number of vertebrae, number of the first closed haemal arches, 
number of keel scales between the base of the ventral fin and the anal aperture, length 
of head and cranium etc.) distinctly indicated that these spent fish agreed in every re- 
spect with the summer or autumn spawning Shetland herring, while the other group 
resembled in all essentials the racial character of the Norwegian spring herring. Thus 
further proof was furnished of the fact that the two great races of ocean herring in 
the northern part of the North Sea meet and mix together, and that it is possible, at 
Stage V. Genitals occupy the whole of the abdominal cavity. Ovaries contain some large 
transparent eggs; milt white, but not yet loose. 
Stage VI. Milt and roe loose. 
Stage VII. Spent. Ovaries slack with some few eggs still remaining. Testicles blood-red. 
It is evident that the above, like any other description of stages in a developement, cannot 
exactly fit every possible case which may occur. This difficulty however, may be met by noting 
the two stages between which the case in question is found to lie, as I—II, III—IV, etc. 
As regards degree of fatness, four stages are recognised. 
0 practically no fat. 
1 some fat. 
-+ moderately fat. 
m very fat. 
*) Norwegische Heringsuntersuchungen während der Jahre 1904—1906. Bergens Museums 
Aarbog, 1908, No. 1. 
**) Vide Brocu, |. c. Tables II, IIL and IV. 
