July of the same year, a great alteration took place in the composition, May showing 
great quantities of fish of the 1906 year. class, June and July of 1907. This can only 
be explained as due to an immigration of new (younger) individuals. It is therefore 
tora Tali ne en 
Fig. 44. Percentage of different stages of maturity in herring samples from the Shetlands, 1912. 
1. June. 2. July. 
Stage II, see note to preceding figure. 
particularly interesting to consider the maturity of these 1911 fish: an illustration of 
this factor will be found in Fig. 43. 
In May there was a large percentage of spent fish, as well as a ee group of indi- 
viduals with genitals at stage III, i.e. preparing to spawn., (called “large herring’ in 
the Norwegian fishery). In June and July the number of the spent fish in the samples 
10* 
