266 
BULLETIN OP THE BUREAU OF FISHERIES 
Table 23. — Variation in number of anal rays 
Locality 
Date 
Number of rays 
Num- 
ber 
Mean 
Prob- 
able 
error 
Standard 
deviation 
of distri- 
bution 
14 
15 
16 
17 
18 
19 
20 
Puget Sound ... 
1927 
— 
5 
40 
37 
11 
1 

94 
16. 61 
0.056 
0.808 
Southeastern Alaska: 
Craig.. 
1925 
2 
7 
45 
37 
6 
3 
100 
16. 47 
.061 
.900 
Whale Bav ... 
1925 
6 
19 
55 
15 
4 
99 
16. 92 
.056 
.817 
Tebenkof Bay. _ ... 
1925 
5 
22 
40 
23 
9 
99 
17. 09 
.068 
1.000 
Point Gardner.. _ 
1925 
.... 
5 
29 
39 
24 
3 
— 
100 
16.91 
.062 
.919 
Total.. __ 
2 
23 
115 
171 
68 
19 
— 
398 
16. 85 
.032 
.950 
Prince William Sound: 
Naked Island 
1925 
3 
17 
38 
10 
7 
75 
17.01 
.074 
.946 
Deep Bay, Elrington Passage 
1925 
4 
8 
20 
12 
1 
45 
16. 96 
.095 
.940 
Prince of Wales Passage (Elrington Passage)... 
1925 
2 
10 
15 
15 
3 
45 
17. 16 
. 099 
.990 
Procession Rocks (Elrington Passage) 
1925 
1 
16 
45 
28 
9 
1 
100 
17.31 
.062 
.915 
McClure Bay 
1927 
i 
1 
11 
30 
24 
7 
.... 
74 
17. 30 
.076 
.967 
Total 
1 
11 
62 
148 
89 
27 
1 
339 
17.17 
.035 
.957 
Dogfish Bay . .. . ... 
1925 
3 
18 
42 
28 
8 
1 
100 
17. 23 
.065 
.970 
Halibut Cove ___ . 
1926 
1 
13 
26 
9 
49 
16. 88 
.069 
.718 
Shuyak Strait 
1925 
1 
9 
49 
73 
21 
2 
155 
16. 71 
.040 
.844 
Unalaska __ 
1928 
1 
13 
18 
s 
40 
16. 82 
. 082 
. 770 
The means of the anal-ray counts do not show the same tendency to change with 
the distance along the coast as is present in the vertebral counts, as shown by Table 24 
which compares the means of the principal localities. There is as great a tendency for 
large differences between adjacent localities as between distant localities. Thus of 
the 11 differences that may have statistical significance, 4 are between adjacent 
localities, and of the 10 differences that probably have no significance 8 are between 
distant localities. 
Table 24. — Comparisons of the means of the anal ray counts of the principal localities 
Localities compared 
Differ- 
ence 
between 
means 
Prob- 
able 
error of 
differ- 
ence 
Differ- 
ence 
divided 
by 
prob- 
able 
error of 
differ- 
ence 
Localities compared 
Differ- 
ence 
between 
means 
Prob- 
able 
error of 
differ- 
ence 
Differ- 
ence 
divided 
by 
prob- 
able 
error of 
differ- 
ence 
Puget Sound and southeastern Alaska 
0.24 
0. 004 
i 3.8 
Southeastern Alaska and Unalaska.. 
0.03 
0.088 
0.3 
Puget Sound and Prince William 
Prince William Sound and Dogfish 
.46 
. 066 
2 7.0 
Bay 
.06 
.074 
.8 
Puget Sound and Dogfish Bay 
.62 
.086 
2 7.2 
Prince William Sound and Halibut 
. 27 
.089 
3. 1 
. 29 
.077 
1 3.8 
Puget Sound and Shuvak Strait.. .. 
. 10 
.072 
1. 4 
Prince William Sound and Shuyak 
. 21 
.099 
2. 1 
. 46 
.058 
2 7. 9 
Southeastern Alaska and Prince Wil- 
Prince William Sound and Unalaska. 
.35 
.089 
i 3.9 
.32 
.047 
i 6.8 
Dogfish Bay and Halibut Cove ___ . 
. 35 
.095 
i 3. 7 
Southeastern Alaska and Dogfish 
Dogfish Bay and Shuyak Strait.. 
.52 
.080 
2 6.5 
.38 
.072 
2 5.3 
Dogfish Bay and Unalaska 
. 41 
. 105 
! 3. 9 
Southeastern Alaska and Halibut 
Halibut Cove and Shuyak Strait 
. 17 
.083 
2.0 
.03 
.076 
.4 
Halibut Cove and Unalaska 
.06 
. 107 
. 6 
Southeastern Alaska and Shuyak 
Shuyak Strait and Unalaska 
. a 
.094 
1.2 
Strait 
. 14 
.056 
2.5 
1 Of probable statistical significance. 1 Possibly a valid racial difference. 
In inquiring into the validity of these differences it may be noted that in Elring- 
ton Passage the means of two samples taken the same year differ by 0.35 ±0.1 13, or 
3.1 probable errors. The maximum variability between any two samples from the 
same locality may well be larger, but at least this provides some measure of the ex- 
pected differences. 
