NOTE Hemandez-Lopez et al.: Age of Octopus vulgaris determined from concentric rings on beaks 
683 
A 
Weight = -735 1.6 +1 607.7 In (no. of rings) 
Pearson’s Correlation: r = 0.8 1 7; r 2 - 0.67 1 
F = 547.09; P < 0.001 ; n = 275 
0 50 100 150 200 250 300 350 400 450 
B VML = -167.52 + 49.566 In (no. of rings) 
Pearson's Correlation: r = 0.775; r 2 - 0.604 
200 1 F = 409.61; P < 0.001; n = 275 
oJ f *6 r- t t t r t t 
0 50 100 150 200 250 300 350 400 450 
Number of rings 
Figure 5 
Plot of the number of rings counted on the lateral walls of the upper beak 
against (A) body weight and (B) ventral mantle length (VML) of benthic 
Octopus vulgaris. 
Acknowledgments 
We thank Ana Y. Martfn-Gutierrez for her assistance in 
data collection. This study was funded by the Secretariat 
for Fishing of the Autonomous Government of the Canary 
Islands (Spain). 
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