Table 2. — Analysis of variance of mean vertebral numbers of juvenile Atlantic 

 menhaden to test for differences within and between localities, 1956-59 



Year class 



Source 

 variation 



Degrees of 

 freedom 



Sum of 

 squares 



Mean 

 square 



1956. 



1957. 



1958. 



1959. 



Localities. 

 Samples .... 

 Individuals 



Localities. 

 Samples .... 

 Individuals 



Localities. 

 Samples. . . . 

 Individuals 



Localities. 

 Samples .... 

 Individuals 



34 



25 



5,652 



33 



57 



8,338 



5 



5 



1,080 



7 



11 



1,773 



181.80 



-4^.81 



1,484.58 



232.79 



41.07 



2,117.28 



15.01 



1.38 



260.29 



24.10 



1.37 



449.81 



5.35 

 1.79 

 0.26 



7.05 

 0.72 

 0.25 



3.00 

 0.28 

 0.24 



3.44 

 0.12 

 0.25 



1 2.99 

 1 6.88 



1 9.79 

 1 2.88 



2 10.71 

 1.17 



1 28.67 

 0.48 



^ P<0.01. 

 2 P<0.05. 



as 



2 



< 



m 



UJ 



ir 



> 



z 

 < 



UJ 



47 I 



46 7 - 



46 50 



46 4 



ft o. *«}• • 



e 



JU i 



DEGREES NORTH LATITUDE 



Figure 2. --Distribution of mean vertebral numbers of juvenile Atlantic menhaden, by latitude, 1956-59. (Sample 

 means for fish of the 1956 yearclass areshown by open circles, 1957 year class by solid dots, 1958 year class by 

 triangles, and 1959 year class by crosses.) 



