SCALES OF THE SPRING SALMON 29 
SESSIONAL PAPER No. 38a 
‘“SrreamM Type ’’—Concluded. 
a eee eee eee ee SE 
LENGTH AT THE END OF 
Year Class. No. 
Ist Year. |2nd Year.|3rd Year.| 4th Year. 
In In In. In 
IC eee I te oct ee Ay ek Co ae 10 BID e| Ra ote ne otal (aes resin 
iB ih cure chanel dct oy oer AOE GON CREM Ene eee ee as Ane 18 3:8 SIs 5 te Ath 
ELIE PE aE. = 9s Sa sack foe ae ae ag ee 44 3-7 14-2 23-7 
EYIEU 9S Give J Sins Soe eee ge ene ae RC ek ee eee | 35 3-7 13-4 22-8 30-0 
PAW CLADE Ey Gee et core Rit Lew hs Kah pte oA) Shieeren 3-7 13-9 23-3 30-0 
Of the mature grilse only four were obtained, all of the “sea type,” in their 
third year. The average for them was: Growth, first year, 11-1; second year, 10-7; 
length at end of first year, 11-1; at end of the second year, 21-8; when caught in 
June, 26-0. 
In the previous paper on “ Growth of spring salmon,” 2 inches was taken as the 
average length when the scale starts to develop. It has been found that this was too 
high for the average, 1.5 inch being much nearer the length. In these calculations, 
therefore, 1-5 inch has been taken from the total length of the fish in each case and 
the rernainder divided in the same proportion as a line drawn from the margin of 
the nucleus to the margin of the scale, would be by the outside limits of the various 
winter checks. To the first year value thus obtained, 1.5 inch is added to get the 
length of the fish at the end of the first year. In making the calculation in this way 
there is no “ phenomenon of apparent change in growth-rate” such as is shown in the 
various herring investigation tables of Hjort, Dahl, and others, making the strained 
explanations by Rosa Lee (Publications de Circonstance, No. 63, Conseil Perm. Int. 
peur l’Expl. de la Mer, 1912) and of Einar Lea (Jbid., No. 66,- 1913) appear 
necessary. 
When the number examined was divided up between the two types and among 
the different classes, the number in any one group was not large enough to make it . 
worth while making graphs, but some points concerning each might be mentioned. 
Taking the “sea type” first, the growth for the first year varies from 7-1 to 12-7 
inches, but very few are less than 8-7. The number 9-3 has the greatest number of 
individuals, but several others have nearly as great. In the second-year growth there 
are some cases abnormally small, 6.2, 6.4, 6.7, 7.2. The majority fall between 8.6 
and 12-2, with 10-0 and 11-1 the most numerous. The length at the end of the second 
year shows much the same variety as the second-year’s growth. There are low ones, 
14.7, 15-8, 16-4, and 16-7, and high ones, 24-1, 24:2, and 24°5, but nearly all come 
between 17-5 and 23-5. The growth in the third year shows much variation between 
the extremes of 3-8 and 4-5 on the one hand, and 11-5 on the other, but the greater 
number come between 7-0 and 8-5. This makes a great variation in length at the 
end of the third year, all the way from 24-2 to 31-8, the majority falling between 
27-5 and 29-5. In the fourth-year growth there is less variation, 4-2 and 6-7 being the 
extremes, but at the end of the year the length varies from 29-9 to 37-9, with one 
abnormally low at 28-3. Those taken in the fifth year were taken at different times 
and a fair comparison can scarcely be made, but with the exception of the abnormal 
one just mentioned, which became only 30-5, there was a variation from 33-0 to 40-0, 
with an average of 35-8. 
