Thresher et at.: Otolith analysis of Nemadactylus macropterus 



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#278 



#366 



#384 



431 



40 



37 

 60001 



___ 350' 



Q. 



c 

 o 



ra 1000 



o 

 U 



1000 



500 



80 160 



Point Number (25um steps) 



Figure 4 



Cross-otolith (primordium to posterior margin) variation in the measured concentrations of the six elements (Ca, 

 Na, Sr, K, S, and CD that could be reliably measured by WD electron-probe microanalysis in Nemadactylus 

 macropterus sagittae. Concentrations are reported in units of ppm by weight for all elements other than Ca, which 

 is reported as percent by weight. Data are adjusted to standards and cleaned of effects of surface pitting and cracks 

 but are otherwise unfiltered. Specimens were chosen randomly from the adult data set and appear to be represen- 

 tative of the variation observed. 



Figure 5 



Auto-correlation analysis of the unfiltered Sr data for the 

 three adult Nemadactylus macropterus of Figure 3, at lags 

 ( intervals between points correlated ) of to 10 points. The 

 correlations become insignificant (P>0.05) at lags of 4 to 6 

 points, varying slightly among specimens. Points are 

 spaced 25 um center-to-center. 



