120 



DEPARTMENT OF THE NATAL SERVICE 



implements. A slight step in this direction may be made by considering the samples 

 taken during the cruise of No. 33 and the samples from Souris. Most of the samples 

 contain many young and immature fish, but, in five, some old fish were found, 

 viz., in the samples from stations 27, 28-29, and 42, and also in one of the trap samples 

 from Souris. The three first stations are situated between the western side of Prince 

 Edward Island and the Gaspe coast, while station 42 lies north of cape George {vide 

 chart, fig. 28). 



Table 6. — Age distribution in three drift-net samples taken off the Gaspe coast 

 (stations 27-29), one trap sample from Souris, P.E.I., and one drift-net sample 

 from west of Port Hood, Cape Breton (station 42), June, 1915. 



Locality and Date. 



Station 27, 48° 21' N., 63" 57' VV., June 



28-29. 

 Station 28, 47° 56' N., 63" 27' W., June 



29-30 

 Station'29, 47" 34' N., 64° 12' W., June 



30July 1. 



Souris, June 7 . . . . 



Station 42, 46^ 0' N., 61° 56' W., June 



15-16. 



Number 



of 

 individ. 



82 

 30 

 95 



117 

 133 



Age-groups — Year-groups. 



3 4 5 6 7 8 9 10 11 12 More 



1912 



1-2 



3-3 



3-2 



25-6 

 07 



1911 



13 4 

 40 



68-4 



36-8 

 64 7 



1910 



1909 



9 8 



67 



3 2 



60 

 38 



1908 



1907 



13-4 



3 3 



h 3 



6 

 15 



1906 



1905 



4-9 

 6-7 



4 :^ 

 07 



19f4 



6 1 

 100 



26 



1903 



3 3 



Table 6 shows the percentual distribution of year-classes in these samples. As 

 already mentioned, there may be some difliculty in determining whether new summer 

 growth has commenced in the case of the older fish. In these samples the scales of 

 some of the younger specimens distinctly show an incipient new growth, whereas in 

 others, judging from the breadth of the last summer zone, it would seem that the 

 new simimer growth had not yet commenced. This being the case with the younger 

 fish, one would hardly expect the scales of the older fish to exhibit any commencement 

 of new summer growth, and, as a matter of fact, the last summer zone on these old 

 scales was found to be of about the same breadth as the previous one. 



The age-tables have therefore been drawn up accordingly, and the column farthest 

 to the left thus includes specimens, some of which exhibit the number of summer 

 zones indicated in the heading, and others an additional narrow zone beyond this. In 

 by far the greater number of the older specimens (from group 7 and upwards) the 

 last summer zone on the scales is taken as representing the summer of 1914. This 

 method of arrangement should, as regards all that is here essential, be correct enough, 

 albeit some doubt may exist in the case of fish of a medium age. 



It will be seen from the table that the fish assigned to the 1903 year-class are 

 relatively numerous, especially in the samples from station 27 ; in three of the samples, 

 the specimens assigned to 1907 are relatively numerous (stations 27-29, and the samples 

 from Souris). The sample from station 42, on the other hand, exhibits no resem- 

 blance to the five gill-net samples from Northumberland strait ; this sample we shall 

 later on have occasion to consider in another connection, and it is merely mentioned 

 here in order to note its difference from the samples from Northumberland strait. 



All samples from these waters point, when taken together, to the correctness of 

 the svipposition that the 1903 and 1907 year-classes were present in greater numbers 

 than the intermediate year-classes of 1908, 1909, and 1910. 



