NORTH AMERICAN SALMONIDAE 



259 



Table 27. — Adjusted rankinps of certain correlated 

 iiicrixtie characters, bii Hpceiex — Continued 



III. Oblique and dor.sal-to-lateral-line scale rows 



To correct for this correlation between the 

 means and their variances, the adjusted rank- 

 injis (table 28) were converted to logarithms. In 

 ordei- to avoid dealiiifr with minus lofrarithms, and 

 witli tiie absence of any logaritlim for a zero rank- 

 ing, all rankings were first increased by 1 and 

 tlieii iiiultipliod by 10. The logaritliins of the 

 rankings so derived are given in table 2t). 



One method of assessing the value of these 

 meristic characters (table 29) is to detei-mine 

 whether the variation within each genus dilfei'S 

 significantly from the variation between genera. 

 Because the number of species varies from genus 

 to genus, calculation of the variance must recog- 

 nize unequal sample size (Snedecor, 1956: p. 268), 

 considering each species as one sample mean. 



Table 28. — Adjusted rankings of meristic indices 



Table 29. — Loyarilhm of adjusted rankings of meristic indices 

 [Rankings: + 1 X IQl 



